Prime factors of given multiplicity in h-free polynomials

DefinitionMonic polynomials of fixed degree#✓fully proved

For a finite field \(F\) and a natural number \(n\), \(M_n\) is the finite set of monic polynomials of degree \(n\) over \(F\): the polynomials \(X^n + c_{n-1} X^{n-1} + \dots + c_1 X + c_0\) with \(c_0, \dots, c_{n-1} \in F\).

public noncomputable def fixedDegreeMonic (F : Type*) [Field F] [Fintype F] [DecidableEq F]
    (n : ℕ) :
    Finset (Polynomial F) :=
  Finset.univ.image fun c : Fin n → F =>
    X ^ n + ∑ i : Fin n, C (c i) * X ^ (i : ℕ)
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Definitions.
Used by 20

TheoremMembership in \(M_n\)#✓fully proved

Let \(F\) be a finite field and \(n \in \mathbb{N}\). A polynomial \(f\) over \(F\) lies in the set \(M_n\) of monic polynomials of degree \(n\) over \(F\) if and only if there are \(c_0, \dots, c_{n-1} \in F\) with \(f = X^n + \sum_{i=0}^{n-1} c_i X^i\).

public theorem mem_fixedDegreeMonic_iff (F : Type*) [Field F] [Fintype F] [DecidableEq F]
    (n : ℕ) (f : Polynomial F) :
    f ∈ fixedDegreeMonic F n ↔
      ∃ c : Fin n → F, X ^ n + ∑ i : Fin n, C (c i) * X ^ (i : ℕ) = f
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Definitions.
Uses 1

TheoremThe only monic polynomial of degree zero#✓fully proved

For every finite field \(F\), the set \(M_0\) of monic polynomials of degree \(0\) over \(F\) is \(\{1\}\).

public theorem fixedDegreeMonic_zero (F : Type*) [Field F] [Fintype F] [DecidableEq F] :
    fixedDegreeMonic F 0 = {1}
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Definitions.
Uses 1 · Used by 2

DefinitionMonic irreducible polynomials#✓fully proved

For a field \(F\), \(\mathcal{P}\) is the set of polynomials over \(F\) that are monic and irreducible; these are the prime polynomials of the paper.

public def monicIrreducible (F : Type*) [Field F] : Set (Polynomial F) :=
  {P | P.Monic ∧ Irreducible P}
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Definitions.
Used by 29
Used byCounting \(\ell\)-free polynomials coprime to an irreducible · Counting \(h\)-full, \(\ell\)-free polynomials coprime to an irreducible · Function field Mertens constant · Series for the function field Mertens constant · \(h\)-free polynomials · Squared prime sum for multiplicity \(k\) on \(h\)-free polynomials · Series formula for the squared prime sum for multiplicity \(k\) on \(h\)-free polynomials · The prime sum \(S_{h,k}\) for multiplicity \(k\) on \(h\)-free polynomials · Series formula for the prime sum \(S_{h,k}\) · The squared prime sum \(U_h\) for multiplicity \(1\) on \(h\)-free polynomials · Series formula for the squared prime sum \(U_h\) · The prime sum \(T_h\) · Unfolding the prime sum \(T_h\) · \(h\)-full polynomials · The Euler product \(\Pi_j\) for \(h\)-full polynomials · Unfolding the Euler product \(\Pi_j\) · The Euler product \(H_{N_h, S_\ell}\) for \(h\)-full, \(\ell\)-free polynomials · Unfolding the Euler product \(H_{N_h, S_\ell}\) · The sum \(\sum_P K(P, h, j)^2\) over monic irreducible polynomials · Unfolding the sum of the squares \(K(P, h, j)^2\) · The constant \(\kappa_j\) for \(h\)-full polynomials · The series defining \(\kappa_j\) · The sum \(\sum_P b_P^2\) over monic irreducible polynomials · The series defining \(\sum_P b_P^2\) · The \(h\)-full prime sum \(\sum_P b_P\) · Formula for the \(h\)-full prime sum \(\sum_P b_P\) · Membership in the set of monic irreducible polynomials · The polynomial \(1\) is \(h\)-free · The polynomial \(1\) is \(h\)-full

TheoremMembership in the set of monic irreducible polynomials#✓fully proved

Let \(F\) be a field. A polynomial \(P\) over \(F\) lies in the set \(\mathcal{P}\) of monic irreducible polynomials over \(F\) if and only if \(P\) is monic and irreducible.

public theorem mem_monicIrreducible_iff (F : Type*) [Field F] (P : Polynomial F) :
    P ∈ monicIrreducible F ↔ P.Monic ∧ Irreducible P
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Definitions.
Uses 1

Definition\(h\)-free polynomials#✓fully proved

Let \(F\) be a field and \(h\) a natural number. The set \(S_h\) of \(h\)-free polynomials over \(F\) consists of the monic polynomials \(f\) over \(F\) such that no monic irreducible polynomial \(P\) over \(F\) satisfies \(P^h \mid f\).

The condition makes sense for every natural number \(h\); the paper's asymptotic theorems separately assume \(h \ge 2\).

public def hFree (F : Type*) [Field F] (h : ℕ) : Set (Polynomial F) :=
  {f | f.Monic ∧ ∀ P ∈ monicIrreducible F, ¬P ^ h ∣ f}
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Definitions.
Uses 1 · Used by 10

TheoremThe polynomial \(1\) is \(h\)-free#✓fully proved

For every field \(F\) and every natural number \(h \ge 1\), the constant polynomial \(1 \in F[X]\) is \(h\)-free: it is monic and no \(h\)-th power of a monic irreducible polynomial divides it.

public theorem one_mem_hFree (F : Type*) [Field F] (h : ℕ) (hh : 0 < h) :
    (1 : Polynomial F) ∈ hFree F h
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Definitions.
Uses 2 · Used by 1

Definition\(h\)-full polynomials#✓fully proved

Let \(F\) be a field and \(h \in \mathbb{N}\). The set \(N_h\) of \(h\)-full polynomials over \(F\) consists of the monic polynomials \(f\) such that \(P^h\) divides \(f\) for every monic irreducible polynomial \(P\) that divides \(f\).

As in the source, theorem statements impose \(h \ge 2\).

public def hFull (F : Type*) [Field F] (h : ℕ) : Set (Polynomial F) :=
  {f | f.Monic ∧ ∀ P ∈ monicIrreducible F, P ∣ f → P ^ h ∣ f}
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Definitions.
Uses 1 · Used by 11

TheoremThe polynomial \(1\) is \(h\)-full#✓fully proved

For every field \(F\) and every natural number \(h\), the constant polynomial \(1 \in F[X]\) is \(h\)-full: it is monic, and whenever a monic irreducible polynomial \(P\) divides it, so does \(P^h\).

The divisibility condition holds vacuously, since no irreducible polynomial divides \(1\).

public theorem one_mem_hFull (F : Type*) [Field F] (h : ℕ) :
    (1 : Polynomial F) ∈ hFull F h
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Definitions.
Uses 2 · Used by 1

DefinitionNumber of prime factors of given multiplicity#✓fully proved

Let \(F\) be a field and \(k \in \mathbb{N}\). For a nonzero polynomial \(f\) over \(F\), \(\omega_k(f)\) is the number of distinct monic irreducible polynomials \(P\) dividing \(f\) whose multiplicity in \(f\) (the largest \(m\) with \(P^m \mid f\)) is exactly \(k\). For the zero polynomial, \(\omega_k(0) = 0\) by convention.

public noncomputable def omegaMult (F : Type*) [Field F] (k : ℕ) (f : Polynomial F) : ℕ := by
  classical
  exact if f = 0 then 0 else
    ((normalizedFactors f).toFinset.filter fun P => (normalizedFactors f).count P = k).card
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Definitions.
Used by 14

Theorem\(\omega_k\) vanishes at the zero polynomial#✓fully proved

For every field \(F\) and every natural number \(k\), \(\omega_k(0) = 0\). Here \(\omega_k(f)\) is the number of distinct monic irreducible polynomials dividing a nonzero polynomial \(f\) over \(F\) with multiplicity exactly \(k\), and \(\omega_k(0) = 0\) by convention, so this records that convention.

public theorem omegaMult_zero (F : Type*) [Field F] (k : ℕ) :
    omegaMult F k 0 = 0
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Definitions.
Uses 1

Theorem\(\omega_k\) vanishes at the polynomial \(1\)#✓fully proved

For every field \(F\) and every natural number \(k\), \(\omega_k(1) = 0\), where \(\omega_k(f)\) is the number of distinct monic irreducible polynomials dividing a nonzero polynomial \(f\) over \(F\) with multiplicity exactly \(k\).

The polynomial \(1\) is a unit, so it has no monic irreducible factors.

public theorem omegaMult_one (F : Type*) [Field F] (k : ℕ) :
    omegaMult F k 1 = 0
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Definitions.
Uses 1 · Used by 2

DefinitionDegree-nondecreasing functions#✓fully proved

Let \(F\) be a field, \(U\) a set of polynomials over \(F\) and \(G\) a real-valued function on polynomials over \(F\). Then \(G\) is degree-nondecreasing on \(U\) when for all \(f_1, f_2 \in U\) with \(\deg f_2 \le \deg f_1\) we have \(G(f_2) \le G(f_1)\). Here \(\deg\) is the natural degree, with \(\deg 0 = 0\).

In particular \(G\) takes the same value on members of \(U\) of equal degree. The natural degree is adequate because \(U\) will consist of monic, hence nonzero, polynomials.

public def IsDegreeNondecreasing (F : Type*) [Field F] (U : Set (Polynomial F))
    (G : Polynomial F → ℝ) : Prop :=
  ∀ ⦃f₁ f₂ : Polynomial F⦄, f₁ ∈ U → f₂ ∈ U → f₂.natDegree ≤ f₁.natDegree →
    G f₂ ≤ G f₁
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 3 (definition preceding the requested normal-order results).
Used by 5

TheoremConstant functions are degree-nondecreasing#✓fully proved

Let \(F\) be a field and \(U\) a set of polynomials over \(F\). For every real number \(c\), the constant function with value \(c\) is degree-nondecreasing on \(U\).

public theorem isDegreeNondecreasing_const (F : Type*) [Field F]
    (U : Set (Polynomial F)) (c : ℝ) :
    IsDegreeNondecreasing F U (fun _ => c)
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 3 (definition preceding the requested normal-order results).
Uses 1

DefinitionNormal order on a set of polynomials#✓fully proved

Let \(F\) be a finite field, let \(U\) be a set of polynomials over \(F\), and let \(g, G\) be real-valued functions on polynomials over \(F\). For \(n \in \mathbb{N}\) let \(M_n\) be the set of monic polynomials of degree \(n\) over \(F\). Then \(g\) has normal order \(G\) on \(U\) when \(g\) and \(G\) are nonnegative on \(U\), \(G\) is degree-nondecreasing on \(U\) (for \(f_1, f_2 \in U\), \(\deg f_2 \le \deg f_1\) implies \(G(f_2) \le G(f_1)\), with \(\deg\) the natural degree), and for every real \(\varepsilon > 0\) the number of \(f \in U \cap M_n\) for which \((1 - \varepsilon)G(f) < g(f) < (1 + \varepsilon)G(f)\) fails is \(o(|U \cap M_n|)\) as \(n \to \infty\).

The paper takes \(g, G : U \to \mathbb{R}_{\ge 0}\); here both are total real-valued functions, with nonnegativity imposed on \(U\).

public noncomputable def HasNormalOrder (F : Type*) [Field F] [Fintype F] [DecidableEq F]
    (U : Set (Polynomial F)) (g G : Polynomial F → ℝ) : Prop := by
  classical
  exact
    (∀ f ∈ U, 0 ≤ g f) ∧ (∀ f ∈ U, 0 ≤ G f) ∧ IsDegreeNondecreasing F U G ∧
      ∀ ε : ℝ, 0 < ε →
        Asymptotics.IsLittleO atTop
          (fun n : ℕ =>
            (((fixedDegreeMonic F n).filter fun f =>
              f ∈ U ∧ ¬((1 - ε) * G f < g f ∧ g f < (1 + ε) * G f)).card : ℝ))
          (fun n : ℕ => (((fixedDegreeMonic F n).filter fun f => f ∈ U).card : ℝ))
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 3 (definition preceding the requested normal-order results).
Uses 2 · Used by 3

TheoremNormal orders are nonnegative#✓fully proved

Let \(F\) be a finite field, \(U\) a set of polynomials over \(F\), and \(g, G\) real-valued functions on polynomials over \(F\). If \(g\) has normal order \(G\) on \(U\), then \(G(f) \ge 0\) for every \(f \in U\).

This is the second defining clause of a normal order.

public theorem HasNormalOrder.nonnegative (F : Type*) [Field F] [Fintype F] [DecidableEq F]
    (U : Set (Polynomial F)) (g G : Polynomial F → ℝ)
    (horder : HasNormalOrder F U g G) (f : Polynomial F) (hf : f ∈ U) :
    0 ≤ G f
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 3 (definition preceding the requested normal-order results).
Uses 3

TheoremErdős–Kac theorem for \(\omega_1\) on \(h\)-free polynomials#●ready to prove

Let \(F\) be a finite field, let \(h \ge 2\) and let \(\alpha \le \beta\) be real numbers. A monic polynomial \(f\) over \(F\) is \(h\)-free if \(P^h \nmid f\) for every monic irreducible \(P\), and \(\omega_1(f)\) is the number of distinct monic irreducible \(P\) that divide \(f\) with multiplicity exactly \(1\). For each \(n\), let \(p_n\) be the number of \(h\)-free monic polynomials \(f\) of degree \(n\) over \(F\) with

\[\alpha \le \frac{\omega_1(f) - \log n}{\sqrt{\log n}} \le \beta,\]

divided by the number of all \(h\)-free monic polynomials of degree \(n\) over \(F\). Then \(p_n \to \frac{1}{\sqrt{2\pi}} \int_\alpha^\beta e^{-t^2/2}\,dt\) as \(n \to \infty\).

MetaMathlibExt.erdosKac_omegaOne_hFree · 15 lines
public theorem_wanted erdosKac_omegaOne_hFree
    (F : Type*) [Field F] [Fintype F] [DecidableEq F]
    (h : ℕ) (hh : 2 ≤ h) (α β : ℝ) (hαβ : α ≤ β) :
    Tendsto
      (fun n : ℕ =>
        (((fixedDegreeMonic F n).filter fun f =>
          f ∈ hFree F h ∧
            α ≤ ((omegaMult F 1 f : ℝ) - Real.log (n : ℝ)) /
              Real.sqrt (Real.log (n : ℝ)) ∧
            ((omegaMult F 1 f : ℝ) - Real.log (n : ℝ)) /
              Real.sqrt (Real.log (n : ℝ)) ≤ β).card : ℝ) /
          (((fixedDegreeMonic F n).filter fun f => f ∈ hFree F h).card : ℝ))
      atTop
      (nhds ((1 / Real.sqrt (2 * Real.pi)) *
        ∫ t : ℝ in α..β, Real.exp (-(t ^ 2) / 2)))
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 2.
Uses 3

Theorem\(\omega_k\) has no normal order on \(h\)-free polynomials for \(1 < k < h\)#●ready to prove

Let \(F\) be a finite field, let \(h \ge 2\) and \(1 < k < h\), and let \(S_h\) be the set of \(h\)-free monic polynomials over \(F\). Let \(G\) be a real-valued function on polynomials over \(F\) that is nonnegative on \(S_h\) and degree-nondecreasing on \(S_h\), that is, \(G(f_2) \le G(f_1)\) whenever \(f_1, f_2 \in S_h\) and \(\deg f_2 \le \deg f_1\). Then \(\omega_k\), the number of monic irreducible factors of multiplicity exactly \(k\), viewed as a real-valued function, does not have normal order \(G\) on \(S_h\).

public theorem_wanted omegaMult_no_normalOrder_hFree
    (F : Type*) [Field F] [Fintype F] [DecidableEq F]
    (h k : ℕ) (hh : 2 ≤ h) (hk₁ : 1 < k) (hkh : k < h)
    (G : Polynomial F → ℝ)
    (hGnonneg : ∀ f ∈ hFree F h, 0 ≤ G f)
    (hGmono : IsDegreeNondecreasing F (hFree F h) G) :
    ¬HasNormalOrder F (hFree F h) (fun f => (omegaMult F k f : ℝ)) G
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 4.
Uses 4

TheoremErdős–Kac theorem for \(\omega_h\) on \(h\)-full polynomials#●ready to prove

Let \(F\) be a finite field, let \(h \ge 2\) and let \(\alpha \le \beta\) be real numbers. A monic polynomial \(f\) over \(F\) is \(h\)-full if \(P^h \mid f\) for every monic irreducible \(P\) dividing \(f\), and \(\omega_h(f)\) is the number of distinct monic irreducible \(P\) that divide \(f\) with multiplicity exactly \(h\). For each \(n\), let \(p_n\) be the number of \(h\)-full monic polynomials \(f\) of degree \(n\) over \(F\) with

\[\alpha \le \frac{\omega_h(f) - \log(n/h)}{\sqrt{\log(n/h)}} \le \beta,\]

divided by the number of all \(h\)-full monic polynomials of degree \(n\) over \(F\), where \(n/h\) is real division. Then \(p_n \to \frac{1}{\sqrt{2\pi}} \int_\alpha^\beta e^{-t^2/2}\,dt\) as \(n \to \infty\).

MetaMathlibExt.erdosKac_omegaH_hFull · 15 lines
public theorem_wanted erdosKac_omegaH_hFull
    (F : Type*) [Field F] [Fintype F] [DecidableEq F]
    (h : ℕ) (hh : 2 ≤ h) (α β : ℝ) (hαβ : α ≤ β) :
    Tendsto
      (fun n : ℕ =>
        (((fixedDegreeMonic F n).filter fun f =>
          f ∈ hFull F h ∧
            α ≤ ((omegaMult F h f : ℝ) - Real.log ((n : ℝ) / (h : ℝ))) /
              Real.sqrt (Real.log ((n : ℝ) / (h : ℝ))) ∧
            ((omegaMult F h f : ℝ) - Real.log ((n : ℝ) / (h : ℝ))) /
              Real.sqrt (Real.log ((n : ℝ) / (h : ℝ))) ≤ β).card : ℝ) /
          (((fixedDegreeMonic F n).filter fun f => f ∈ hFull F h).card : ℝ))
      atTop
      (nhds ((1 / Real.sqrt (2 * Real.pi)) *
        ∫ t : ℝ in α..β, Real.exp (-(t ^ 2) / 2)))
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 6.
Uses 3

Theorem\(\omega_k\) has no normal order on \(h\)-full polynomials for \(k > h\)#●ready to prove

Let \(F\) be a finite field, let \(2 \le h < k\), and let \(N_h\) be the set of \(h\)-full monic polynomials over \(F\). Let \(G\) be a real-valued function on polynomials over \(F\) that is nonnegative on \(N_h\) and degree-nondecreasing on \(N_h\), that is, \(G(f_2) \le G(f_1)\) whenever \(f_1, f_2 \in N_h\) and \(\deg f_2 \le \deg f_1\). Then \(\omega_k\), the number of monic irreducible factors of multiplicity exactly \(k\), viewed as a real-valued function, does not have normal order \(G\) on \(N_h\).

public theorem_wanted omegaMult_no_normalOrder_hFull
    (F : Type*) [Field F] [Fintype F] [DecidableEq F]
    (h k : ℕ) (hh : 2 ≤ h) (hhk : h < k)
    (G : Polynomial F → ℝ)
    (hGnonneg : ∀ f ∈ hFull F h, 0 ≤ G f)
    (hGmono : IsDegreeNondecreasing F (hFull F h) G) :
    ¬HasNormalOrder F (hFull F h) (fun f => (omegaMult F k f : ℝ)) G
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 8.
Uses 4

TheoremCounting \(\ell\)-free polynomials coprime to an irreducible#●ready to prove

Let \(F\) be a finite field with \(q\) elements, let \(\ell \ge 2\) and let \(d\) be a natural number. Call a monic polynomial over \(F\) \(\ell\)-free if it is divisible by the \(\ell\)-th power of no monic irreducible polynomial. There is a constant \(C \ge 0\) such that for every monic irreducible polynomial \(P\) over \(F\) of degree \(d\), with \(|P| = q^{d}\), and every natural number \(n\), the number \(N\) of \(\ell\)-free monic polynomials of degree \(n\) over \(F\) that are coprime to \(P\) satisfies

\[\left| N - \frac{q^n (1 - q^{1-\ell})(1 - |P|^{-1})}{1 - |P|^{-\ell}} \right| \le C.\]

So \(C\) depends on \(F\), \(\ell\) and \(d\) but not on \(P\) or \(n\).

The source states the lemma for \(\ell > 0\). The factor \(1 - q^{1-\ell}\) equals \(1/\zeta_q(\ell)\), where \(\zeta_q(s) = 1/(1 - q^{1-s})\) is the zeta function of the polynomial ring over \(F\); it has a pole at \(s = 1\), so the statement here assumes \(\ell \ge 2\).

public theorem_wanted card_hFree_coprime_irreducible_asymptotic
    (F : Type*) [Field F] [Fintype F] [DecidableEq F]
    (ℓ : ℕ) (hℓ : 2 ≤ ℓ) (d : ℕ) :
    ∃ C : ℝ, 0 ≤ C ∧ ∀ P ∈ monicIrreducible F, P.natDegree = d → ∀ n : ℕ,
      |(((fixedDegreeMonic F n).filter fun f =>
          f ∈ hFree F ℓ ∧ IsCoprime f P).card : ℝ) -
        ((Fintype.card F : ℝ) ^ n *
          (1 - (Fintype.card F : ℝ) ^ (1 - (ℓ : ℤ))) *
          (1 - ((Fintype.card F : ℝ) ^ P.natDegree)⁻¹) /
          (1 - (((Fintype.card F : ℝ) ^ P.natDegree) ^ ℓ)⁻¹))| ≤ C
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Lemma 3.
Uses 3

TheoremPerron's formula for degree slices of monic polynomials#●ready to prove

Let \(F\) be a finite field, let \(M_m\) be the set of monic polynomials of degree \(m\) over \(F\), let \(a \colon F[X] \to \mathbb{C}\), and write \(c_m = \sum_{f \in M_m} a(f)\). Let \(r\) be a real number with \(0 < r < 1\) such that the series \(\sum_{m \ge 0} |c_m| r^m\) converges, and let \(A \colon \mathbb{C} \to \mathbb{C}\) satisfy \(A(u) = \sum_{m \ge 0} c_m u^m\) for every complex \(u\) with \(|u| = r\). Then for every \(n \ge 0\),

\[c_n = \frac{1}{2\pi i} \oint_{|u| = r} \frac{A(u)}{u^{n+1}}\, du,\]

where the circle \(|u| = r\) is traversed once counterclockwise.

Convergence of \(\sum |c_m| r^m\) at the single radius \(r\) stands in for the paper's uniform absolute convergence on the closed disk, and \(A\) only has to agree with the series on the circle, the only values the contour integral sees.

public theorem_wanted perron_formula_polynomial_degree_slice
    (F : Type*) [Field F] [Fintype F] [DecidableEq F]
    (a : Polynomial F → ℂ) (A : ℂ → ℂ) (r : ℝ)
    (hr₀ : 0 < r) (hr₁ : r < 1)
    (hsum : Summable fun n : ℕ =>
      ‖∑ f ∈ fixedDegreeMonic F n, a f‖ * r ^ n)
    (hA : ∀ u : ℂ, ‖u‖ = r → A u = ∑' m : ℕ,
      (∑ f ∈ fixedDegreeMonic F m, a f) * u ^ m)
    (n : ℕ) :
    (∑ f ∈ fixedDegreeMonic F n, a f) =
      (1 / (2 * Real.pi * Complex.I)) *
        ∮ u in C(0, r), A u / u ^ (n + 1)
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 9.
Uses 1

DefinitionThe polynomial norm \(q^{\deg f}\) over a finite field#✓fully proved

Let \(F\) be a finite field with \(q\) elements. The norm of a polynomial \(f \in F[X]\) is the real number \(|f| = q^{\deg f}\) if \(f \neq 0\), and \(|0| = 0\).

public noncomputable def polyNorm (F : Type*) [Field F] [Fintype F] (f : Polynomial F) : ℝ :=
  if f = 0 then 0 else (Fintype.card F : ℝ) ^ f.natDegree
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Introduction.
Used by 22

TheoremThe zero polynomial has norm \(0\)#✓fully proved

For every finite field \(F\), the norm of the zero polynomial in \(F[X]\) is \(|0| = 0\).

public theorem polyNorm_zero (F : Type*) [Field F] [Fintype F] : polyNorm F 0 = 0
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Introduction.
Uses 1

TheoremA nonzero polynomial has norm \(q^{\deg f}\)#✓fully proved

Let \(F\) be a finite field with \(q\) elements. Every nonzero polynomial \(f \in F[X]\) has norm \(|f| = q^{\deg f}\).

public theorem polyNorm_of_ne_zero (F : Type*) [Field F] [Fintype F] {f : Polynomial F}
    (hf : f ≠ 0) : polyNorm F f = (Fintype.card F : ℝ) ^ f.natDegree
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Introduction.
Uses 1

DefinitionFunction field Mertens constant#✓fully proved

For a finite field \(F\) with \(q\) elements, the analogue of the first Mertens constant is

\[B_1 = \gamma + \sum_P \left(\log\left(1 - \frac{1}{|P|}\right) + \frac{1}{|P|}\right),\]

where \(\gamma\) is the Euler–Mascheroni constant, the sum runs over the monic irreducible polynomials \(P\) over \(F\), and \(|P| = q^{\deg P}\).

public noncomputable def functionFieldMertensConstant (F : Type*) [Field F] [Fintype F] : ℝ :=
  Real.eulerMascheroniConstant +
    ∑' P : monicIrreducible F, (Real.log (1 - 1 / polyNorm F P) + 1 / polyNorm F P)
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Introduction.
Uses 2 · Used by 7

TheoremSeries for the function field Mertens constant#✓fully proved

For a finite field \(F\) with \(q\) elements, the function field Mertens constant \(B_1\) of \(F\) equals

\[\gamma + \sum_P \left(\log\left(1 - \frac{1}{|P|}\right) + \frac{1}{|P|}\right),\]

where \(\gamma\) is the Euler–Mascheroni constant, the sum runs over the monic irreducible polynomials \(P\) over \(F\), and \(|P| = q^{\deg P}\).

public theorem functionFieldMertensConstant_eq (F : Type*) [Field F] [Fintype F] :
    functionFieldMertensConstant F = Real.eulerMascheroniConstant +
      ∑' P : monicIrreducible F, (Real.log (1 - 1 / polyNorm F P) + 1 / polyNorm F P)
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Introduction.
Uses 3

DefinitionMoments of \(\omega_k\) over \(h\)-free polynomials#✓fully proved

Let \(F\) be a finite field and let \(h\), \(k\), \(j\), \(n\) be natural numbers. Let \(S_h\) be the set of \(h\)-free monic polynomials over \(F\) (those divisible by no \(P^h\) with \(P\) monic irreducible), \(M_n\) the set of monic polynomials of degree \(n\) over \(F\), and \(\omega_k(f)\) the number of distinct monic irreducible factors of \(f\) whose multiplicity is exactly \(k\). The \(j\)-th moment of \(\omega_k\) over the \(h\)-free monic polynomials of degree \(n\) is the real number

\[\frac{1}{|S_h \cap M_n|} \sum_{f \in S_h \cap M_n} \omega_k(f)^j,\]

which is \(0\) when \(S_h \cap M_n\) is empty.

public noncomputable def hFreeMoment (F : Type*) [Field F] [Fintype F] [DecidableEq F]
    (h k j n : ℕ) : ℝ :=
  (∑ f ∈ (fixedDegreeMonic F n).filter (· ∈ hFree F h), (omegaMult F k f : ℝ) ^ j) /
    (((fixedDegreeMonic F n).filter (· ∈ hFree F h)).card : ℝ)
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorems 1 and 3.
Uses 3 · Used by 6

TheoremExplicit formula for the moments over h-free polynomials#✓fully proved

Let \(F\) be a finite field and let \(h, k, j, n\) be natural numbers. Write \(M_n\) for the monic polynomials of degree \(n\) over \(F\), \(S_h\) for the \(h\)-free monic polynomials (those divisible by the \(h\)-th power of no monic irreducible polynomial) and \(\omega_k(f)\) for the number of distinct monic irreducible factors of \(f\) of multiplicity exactly \(k\). Then the \(j\)-th moment of \(\omega_k\) over \(S_h \cap M_n\) equals

\[\frac{1}{|S_h \cap M_n|} \sum_{f \in S_h \cap M_n} \omega_k(f)^j,\]

which is \(0\) when \(S_h \cap M_n\) is empty.

public theorem hFreeMoment_eq (F : Type*) [Field F] [Fintype F] [DecidableEq F]
    (h k j n : ℕ) : hFreeMoment F h k j n =
      (∑ f ∈ (fixedDegreeMonic F n).filter (· ∈ hFree F h), (omegaMult F k f : ℝ) ^ j) /
        (((fixedDegreeMonic F n).filter (· ∈ hFree F h)).card : ℝ)
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorems 1 and 3.
Uses 4

DefinitionThe prime sum \(T_h\)#✓fully proved

Let \(F\) be a finite field with \(q\) elements, let \(h\) be a natural number, and write \(|P| = q^{\deg P}\) for a monic irreducible polynomial \(P\) over \(F\). The prime sum \(T_h\) is the real number

\[T_h = \sum_P \frac{|P|^{h-1} - 1}{|P|\,(|P|^h - 1)},\]

the sum running over all monic irreducible polynomials \(P\) over \(F\), where, when \(h = 0\), the exponent \(h - 1\) is read as \(0\) and each summand, whose denominator then vanishes, is read as \(0\); the sum is taken to be \(0\) if it does not converge absolutely. For \(h \ge 2\) it is the prime sum in the constant term of the mean number of monic irreducible factors of multiplicity exactly one of a monic \(h\)-free polynomial of degree \(n\) (Theorem 1).

public noncomputable def hFreeOmegaOneSum (F : Type*) [Field F] [Fintype F] (h : ℕ) : ℝ :=
  ∑' P : monicIrreducible F,
    (polyNorm F P ^ (h - 1) - 1) / (polyNorm F P * (polyNorm F P ^ h - 1))
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 1.
Uses 2 · Used by 4

TheoremUnfolding the prime sum \(T_h\)#✓fully proved

Let \(F\) be a finite field with \(q\) elements, let \(h\) be a natural number, and write \(|P| = q^{\deg P}\) for a monic irreducible polynomial \(P\) over \(F\). Then the prime sum \(T_h\) equals the real sum over all monic irreducible polynomials \(P\) over \(F\)

\[\sum_P \frac{|P|^{h-1} - 1}{|P|\,(|P|^h - 1)},\]

where, when \(h = 0\), the exponent \(h - 1\) is read as \(0\) and each summand, whose denominator then vanishes, is read as \(0\); the sum is taken to be \(0\) if it does not converge absolutely.

public theorem hFreeOmegaOneSum_eq (F : Type*) [Field F] [Fintype F] (h : ℕ) :
    hFreeOmegaOneSum F h = ∑' P : monicIrreducible F,
      (polyNorm F P ^ (h - 1) - 1) / (polyNorm F P * (polyNorm F P ^ h - 1))
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 1.
Uses 3

DefinitionThe squared prime sum \(U_h\) for multiplicity \(1\) on \(h\)-free polynomials#✓fully proved

Let \(F\) be a finite field with \(q\) elements, let \(h\) be a natural number, and for a monic irreducible polynomial \(P\) over \(F\) write \(|P| = q^{\deg P}\). Then \(U_h\) is the real number

\[U_h = \sum_P \left(\frac{|P|^{\max(h-2,\,0)} (|P| - 1)}{|P|^h - 1}\right)^2,\]

the sum over all monic irreducible \(P\), where a quotient with zero denominator (only when \(h = 0\)) is read as \(0\) and the sum is \(0\) when the series does not converge absolutely.

\(U_h\) enters the constants in the second moment and the variance of the number of distinct monic irreducible factors of multiplicity exactly \(1\) over \(h\)-free polynomials.

public noncomputable def hFreeOmegaOneSqSum (F : Type*) [Field F] [Fintype F] (h : ℕ) : ℝ :=
  ∑' P : monicIrreducible F,
    (polyNorm F P ^ (h - 2) * (polyNorm F P - 1) / (polyNorm F P ^ h - 1)) ^ 2
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 1.
Uses 2 · Used by 3

TheoremSeries formula for the squared prime sum \(U_h\)#✓fully proved

Let \(F\) be a finite field with \(q\) elements, let \(h\) be a natural number, and for a monic irreducible polynomial \(P\) over \(F\) write \(|P| = q^{\deg P}\). Then the squared prime sum \(U_h\) for multiplicity \(1\) on \(h\)-free polynomials equals

\[\sum_P \left(\frac{|P|^{\max(h-2,\,0)} (|P| - 1)}{|P|^h - 1}\right)^2,\]

the sum over all monic irreducible \(P\), where a quotient with zero denominator (only when \(h = 0\)) is read as \(0\) and the sum is \(0\) when the series does not converge absolutely.

public theorem hFreeOmegaOneSqSum_eq (F : Type*) [Field F] [Fintype F] (h : ℕ) :
    hFreeOmegaOneSqSum F h = ∑' P : monicIrreducible F,
      (polyNorm F P ^ (h - 2) * (polyNorm F P - 1) / (polyNorm F P ^ h - 1)) ^ 2
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 1.
Uses 3

DefinitionThe prime sum \(S_{h,k}\) for multiplicity \(k\) on \(h\)-free polynomials#✓fully proved

Let \(F\) be a finite field with \(q\) elements and let \(h\), \(k\) be natural numbers. For a monic irreducible polynomial \(P\) over \(F\) write \(|P| = q^{\deg P}\) and \(a_P = |P|^{\max(h-k-1,\,0)} (|P| - 1)/(|P|^h - 1)\), read as \(0\) when the denominator vanishes (only when \(h = 0\)). Then \(S_{h,k}\) is the real number \(\sum_P a_P\), the sum over all monic irreducible \(P\), taken to be \(0\) when the series does not converge absolutely.

public noncomputable def hFreeOmegaMultSum (F : Type*) [Field F] [Fintype F] (h k : ℕ) : ℝ :=
  ∑' P : monicIrreducible F,
    polyNorm F P ^ (h - k - 1) * (polyNorm F P - 1) / (polyNorm F P ^ h - 1)
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 3.
Uses 2 · Used by 3

TheoremSeries formula for the prime sum \(S_{h,k}\)#✓fully proved

Let \(F\) be a finite field with \(q\) elements and let \(h\), \(k\) be natural numbers. For a monic irreducible polynomial \(P\) over \(F\) write \(|P| = q^{\deg P}\) and \(a_P = |P|^{\max(h-k-1,\,0)} (|P| - 1)/(|P|^h - 1)\), read as \(0\) when the denominator vanishes (only when \(h = 0\)). Then the prime sum \(S_{h,k}\) for multiplicity \(k\) on \(h\)-free polynomials equals \(\sum_P a_P\), the sum over all monic irreducible \(P\), taken to be \(0\) when the series does not converge absolutely.

public theorem hFreeOmegaMultSum_eq (F : Type*) [Field F] [Fintype F] (h k : ℕ) :
    hFreeOmegaMultSum F h k = ∑' P : monicIrreducible F,
      polyNorm F P ^ (h - k - 1) * (polyNorm F P - 1) / (polyNorm F P ^ h - 1)
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 3.
Uses 3

DefinitionSquared prime sum for multiplicity \(k\) on \(h\)-free polynomials#✓fully proved

Let \(F\) be a finite field with \(q\) elements and let \(h\), \(k\) be natural numbers. For a monic irreducible polynomial \(P\) over \(F\) write \(|P| = q^{\deg P}\) and \(a_P = |P|^{\max(h-k-1,\,0)} (|P| - 1)/(|P|^h - 1)\), read as \(0\) when the denominator vanishes (only when \(h = 0\)). The squared prime sum is the real number \(\sum_P a_P^2\), the sum over all monic irreducible \(P\), taken to be \(0\) when the series does not converge absolutely.

public noncomputable def hFreeOmegaMultSqSum (F : Type*) [Field F] [Fintype F] (h k : ℕ) : ℝ :=
  ∑' P : monicIrreducible F,
    (polyNorm F P ^ (h - k - 1) * (polyNorm F P - 1) / (polyNorm F P ^ h - 1)) ^ 2
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 3.
Uses 2 · Used by 2

TheoremSeries formula for the squared prime sum for multiplicity \(k\) on \(h\)-free polynomials#✓fully proved

Let \(F\) be a finite field with \(q\) elements and let \(h\), \(k\) be natural numbers. For a monic irreducible polynomial \(P\) over \(F\) write \(|P| = q^{\deg P}\) and \(a_P = |P|^{\max(h-k-1,\,0)} (|P| - 1)/(|P|^h - 1)\), read as \(0\) when the denominator vanishes (only when \(h = 0\)). Then the squared prime sum for multiplicity \(k\) on \(h\)-free polynomials equals \(\sum_P a_P^2\), the sum over all monic irreducible \(P\), taken to be \(0\) when the series does not converge absolutely.

public theorem hFreeOmegaMultSqSum_eq (F : Type*) [Field F] [Fintype F] (h k : ℕ) :
    hFreeOmegaMultSqSum F h k = ∑' P : monicIrreducible F,
      (polyNorm F P ^ (h - k - 1) * (polyNorm F P - 1) / (polyNorm F P ^ h - 1)) ^ 2
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 3.
Uses 3

TheoremMean of \(\omega_1\) over \(h\)-free polynomials#●ready to prove

Let \(F\) be a finite field with \(q\) elements and let \(h \ge 2\). Let \(\omega_1(f)\) be the number of monic irreducible \(P\) dividing \(f\) exactly once, write \(|P| = q^{\deg P}\), and let \(B_1 = \gamma + \sum_P (\log(1 - 1/|P|) + 1/|P|)\) be the function field Mertens constant, with \(\gamma\) the Euler–Mascheroni constant, and let \(T_h = \sum_P (|P|^{h-1} - 1)/(|P|(|P|^h - 1))\), both sums over monic irreducible \(P\). Then the mean of \(\omega_1\) over the \(h\)-free monic polynomials of degree \(n\) over \(F\) is \(\log n + B_1 - T_h + O(1/n)\) as \(n \to \infty\).

public theorem_wanted omegaOne_hFree_mean_asymptotic
    (F : Type*) [Field F] [Fintype F] [DecidableEq F] (h : ℕ) (hh : 2 ≤ h) :
    (fun n : ℕ => hFreeMoment F h 1 1 n -
        (Real.log n + (functionFieldMertensConstant F - hFreeOmegaOneSum F h)))
      =O[atTop] (fun n : ℕ => 1 / (n : ℝ))
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 1, Equation (4).
Uses 3

TheoremSecond moment of \(\omega_1\) over \(h\)-free polynomials#●ready to prove

Let \(F\) be a finite field with \(q\) elements, let \(h \ge 2\) and let \(\varepsilon > 0\). Let \(\omega_1(f)\) be the number of monic irreducible \(P\) dividing \(f\) exactly once, write \(S_h \cap M_n\) for the set of \(h\)-free monic polynomials of degree \(n\) over \(F\) and \(|P| = q^{\deg P}\), and let \(B_1 = \gamma + \sum_P (\log(1 - 1/|P|) + 1/|P|)\) be the function field Mertens constant, with \(\gamma\) the Euler–Mascheroni constant, \(T_h = \sum_P (|P|^{h-1} - 1)/(|P|(|P|^h - 1))\) and \(U_h = \sum_P (|P|^{h-2}(|P| - 1)/(|P|^h - 1))^2\), all sums over monic irreducible \(P\). Then the mean of \(\omega_1^2\) over \(S_h \cap M_n\) is \(\log^2 n + C_2 \log n + C_3 + O(n^{\varepsilon - 1})\) as \(n \to \infty\), where \(C_2 = 2(B_1 - T_h) + 1\) and \(C_3 = B_1^2 + B_1 - \pi^2/6 - U_h + T_h^2 - (2B_1 + 1) T_h\).

The printed error \(O_\varepsilon(q^n/n^{1-\varepsilon})\) is the error of the unnormalized sum in the paper's proof; divided by \(|S_h \cap M_n| = q^n/\zeta_q(h)\) for \(n \ge h\), where \(\zeta_q(h) = (1 - q^{1-h})^{-1}\), it is \(O_\varepsilon(n^{\varepsilon-1})\), the order that the paper's remark (an extra factor \(n^\varepsilon\) over the first moment's \(O(1/n)\)) and its variance formula state.

public theorem_wanted omegaOne_hFree_secondMoment_asymptotic
    (F : Type*) [Field F] [Fintype F] [DecidableEq F] (h : ℕ) (hh : 2 ≤ h) (ε : ℝ)
    (hε : 0 < ε) :
    (fun n : ℕ => hFreeMoment F h 1 2 n -
        (Real.log n ^ 2 +
          (2 * (functionFieldMertensConstant F - hFreeOmegaOneSum F h) + 1) * Real.log n +
          (functionFieldMertensConstant F ^ 2 + functionFieldMertensConstant F - Real.pi ^ 2 / 6 -
            hFreeOmegaOneSqSum F h + hFreeOmegaOneSum F h ^ 2 -
            (2 * functionFieldMertensConstant F + 1) * hFreeOmegaOneSum F h)))
      =O[atTop] (fun n : ℕ => (n : ℝ) ^ (ε - 1))
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 1, Equation (5).
Uses 4

TheoremVariance of \(\omega_1\) over \(h\)-free polynomials#●ready to prove

Let \(F\) be a finite field with \(q\) elements, let \(h \ge 2\) and let \(\varepsilon > 0\). Let \(\omega_1(f)\) be the number of monic irreducible \(P\) dividing \(f\) exactly once, write \(|P| = q^{\deg P}\), and let \(B_1 = \gamma + \sum_P (\log(1 - 1/|P|) + 1/|P|)\) be the function field Mertens constant, with \(\gamma\) the Euler–Mascheroni constant, \(T_h = \sum_P (|P|^{h-1} - 1)/(|P|(|P|^h - 1))\) and \(U_h = \sum_P (|P|^{h-2}(|P| - 1)/(|P|^h - 1))^2\), all sums over monic irreducible \(P\). Then the variance of \(\omega_1\) over the \(h\)-free monic polynomials of degree \(n\) over \(F\), that is, the mean of \(\omega_1^2\) minus the square of the mean of \(\omega_1\), is \(\log n + B_1 - \pi^2/6 - U_h - T_h + O(n^{\varepsilon - 1})\) as \(n \to \infty\).

public theorem_wanted omegaOne_hFree_variance_asymptotic
    (F : Type*) [Field F] [Fintype F] [DecidableEq F] (h : ℕ) (hh : 2 ≤ h) (ε : ℝ)
    (hε : 0 < ε) :
    (fun n : ℕ => hFreeMoment F h 1 2 n - hFreeMoment F h 1 1 n ^ 2 -
        (Real.log n + (functionFieldMertensConstant F - Real.pi ^ 2 / 6 -
          hFreeOmegaOneSqSum F h - hFreeOmegaOneSum F h)))
      =O[atTop] (fun n : ℕ => (n : ℝ) ^ (ε - 1))
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 1.
Uses 4

TheoremMean of \(\omega_k\) over \(h\)-free polynomials#●ready to prove

Let \(F\) be a finite field with \(q\) elements, let \(h, k\) be natural numbers with \(1 < k < h\), and let \(\varepsilon > 0\). Write \(S_h \cap M_n\) for the set of monic polynomials \(f\) of degree \(n\) over \(F\) that are \(h\)-free (no \(P^h\) with \(P\) monic irreducible divides \(f\)), and \(\omega_k(f)\) for the number of monic irreducible \(P\) that divide \(f\) exactly \(k\) times. For monic irreducible \(P\) put \(|P| = q^{\deg P}\) and \(a_P = |P|^{h-k-1}(|P| - 1)/(|P|^h - 1)\), and let \(S_{h,k} = \sum_P a_P\), the sum over monic irreducible \(P\). Then, as \(n \to \infty\), the mean of \(\omega_k\) over \(S_h \cap M_n\) is \(S_{h,k} + O(q^{n/k - n + \varepsilon n})\).

public theorem_wanted omegaMult_hFree_mean_asymptotic
    (F : Type*) [Field F] [Fintype F] [DecidableEq F] (h k : ℕ) (hk : 1 < k) (hkh : k < h)
    (ε : ℝ) (hε : 0 < ε) :
    (fun n : ℕ => hFreeMoment F h k 1 n - hFreeOmegaMultSum F h k)
      =O[atTop] (fun n : ℕ => (Fintype.card F : ℝ) ^ ((n : ℝ) / k - n + ε * n))
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 3, Equation (6).
Uses 2

TheoremSecond moment of \(\omega_k\) over \(h\)-free polynomials#●ready to prove

Let \(F\) be a finite field with \(q\) elements, let \(h, k\) be natural numbers with \(1 < k < h\), and let \(\varepsilon > 0\). Write \(S_h \cap M_n\) for the set of monic polynomials \(f\) of degree \(n\) over \(F\) that are \(h\)-free (no \(P^h\) with \(P\) monic irreducible divides \(f\)), and \(\omega_k(f)\) for the number of monic irreducible \(P\) that divide \(f\) exactly \(k\) times. For monic irreducible \(P\) put \(|P| = q^{\deg P}\) and \(a_P = |P|^{h-k-1}(|P| - 1)/(|P|^h - 1)\), and let \(S_{h,k} = \sum_P a_P\), the sum over monic irreducible \(P\). Then, as \(n \to \infty\), the mean of \(\omega_k^2\) over \(S_h \cap M_n\) is \(S_{h,k}^2 - \sum_P a_P^2 + S_{h,k} + O(q^{n/k - n + \varepsilon n})\).

public theorem_wanted omegaMult_hFree_secondMoment_asymptotic
    (F : Type*) [Field F] [Fintype F] [DecidableEq F] (h k : ℕ) (hk : 1 < k) (hkh : k < h)
    (ε : ℝ) (hε : 0 < ε) :
    (fun n : ℕ => hFreeMoment F h k 2 n -
        (hFreeOmegaMultSum F h k ^ 2 - hFreeOmegaMultSqSum F h k + hFreeOmegaMultSum F h k))
      =O[atTop] (fun n : ℕ => (Fintype.card F : ℝ) ^ ((n : ℝ) / k - n + ε * n))
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 3, Equation (7).
Uses 3

TheoremDerivatives at \(z = 1\) of uniform approximations#●ready to prove

Let \(r > 0\), let \(D\) be the open disk of radius \(r\) centred at \(1\) in \(\mathbb{C}\), and let \(f\) and \(G_n\) (\(n \in \mathbb{N}\)) be complex functions analytic on \(D\). Suppose there is a real constant \(C\) such that \(|G_n(z) - f(z)\, n^{z-1}| \le C\, n^{\operatorname{Re} z - 2}\) for all \(n \ge 1\) and all \(z \in D\). Then for every \(k \in \mathbb{N}\) and every \(\varepsilon > 0\), as \(n \to \infty\),

\[G_n^{(k)}(1) - \frac{d^k}{dz^k}\big(f(z)\, n^{z-1}\big)\Big|_{z=1} = O(n^{\varepsilon - 1}).\]

This is the paper's Lemma 1, a corrected version of Lalín and Zhang's Lemma 3.2; Equation (11) is the case \(k = 1\). The paper's "analytic at \(z = 1\)" with an error term "in a neighborhood of \(z = 1\)" is read as analyticity on a fixed disk on which the bound holds with one constant for all \(n \ge 1\).

public theorem_wanted iteratedDeriv_sub_isBigO_of_uniform_approx
    (G : ℕ → ℂ → ℂ) (f : ℂ → ℂ) (r : ℝ) (hr : 0 < r)
    (hG : ∀ n, AnalyticOnNhd ℂ (G n) (Metric.ball 1 r))
    (hf : AnalyticOnNhd ℂ f (Metric.ball 1 r))
    (hbound : ∃ C : ℝ, ∀ n : ℕ, 1 ≤ n → ∀ z ∈ Metric.ball (1 : ℂ) r,
      ‖G n z - f z * (n : ℂ) ^ (z - 1)‖ ≤ C * (n : ℝ) ^ (z.re - 2))
    (k : ℕ) (ε : ℝ) (hε : 0 < ε) :
    (fun n : ℕ => iteratedDeriv k (G n) 1 -
        iteratedDeriv k (fun z => f z * (n : ℂ) ^ (z - 1)) 1)
      =O[atTop] (fun n : ℕ => (n : ℝ) ^ (ε - 1))
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Lemma 1.

TheoremSelberg–Delange theorem for function fields#●ready to prove

Let \(q > 1\) and \(A > 0\) be real numbers, and let \(B_z(n)\) and \(C_z(n)\) be complex numbers, for \(z \in \mathbb{C}\) and integers \(n \ge 0\), such that for all \(z\) and \(n\)

\[C_z(n) = \sum_{a=0}^{n} B_z(a)\, q^{n-a} \frac{(z)_{n-a}}{(n-a)!},\]

where \((z)_m = z(z+1)\cdots(z+m-1)\) is the rising factorial. Suppose there is a constant \(M\) such that for every complex \(z\) with \(|z| \le A\) the series \(\sum_{n \ge 0} |B_z(n)| (n+1)^{2A+2} q^{-n}\) converges and its sum is at most \(M\). Then there is a constant \(K\) such that for every complex \(z\) with \(|z| \le A\) and every integer \(n \ge 1\),

\[\left| C_z(n) - \frac{q^n n^{z-1}}{\Gamma(z)} \sum_{a \ge 0} \frac{B_z(a)}{q^a} \right| \le K q^n n^{\operatorname{Re} z - 2}.\]

In terms of the generating functions \(B(u, z) = \sum_{n \ge 0} B_z(n) u^n\) and \(C(u, z) = \sum_{n \ge 0} C_z(n) u^n\), and with \(Z_q(u) = (1 - qu)^{-1}\), the hypothesis on \(C_z(n)\) says \(C(u, z) = B(u, z) Z_q(u)^z\), and the main term is \(q^n n^{z-1} B(1/q, z)/\Gamma(z)\). The paper's \(q\) is the size of the field. The weight \((n+1)^{2A+2}\) replaces the paper's \(n^{2A+2}\): equivalent for \(n \ge 1\), it also bounds \(B_z(0)\) uniformly, without which the conclusion fails (unbounded \(B_z(0)\) along \(z \to 2\) with \(A = 2\)).

public theorem_wanted selbergDelange_functionField
    (q : ℝ) (hq : 1 < q) (A : ℝ) (hA : 0 < A) (B Cz : ℂ → ℕ → ℂ)
    (hC : ∀ z n, Cz z n = ∑ a ∈ Finset.range (n + 1),
      B z a * (q : ℂ) ^ (n - a) * (ascPochhammer ℂ (n - a)).eval z / ((n - a).factorial : ℂ))
    (hB : ∃ M : ℝ, ∀ z : ℂ, ‖z‖ ≤ A →
      Summable (fun n : ℕ => ‖B z n‖ * ((n : ℝ) + 1) ^ (2 * A + 2) / q ^ n) ∧
        ∑' n : ℕ, ‖B z n‖ * ((n : ℝ) + 1) ^ (2 * A + 2) / q ^ n ≤ M) :
    ∃ K : ℝ, ∀ z : ℂ, ‖z‖ ≤ A → ∀ n : ℕ, 1 ≤ n →
      ‖Cz z n - (q : ℂ) ^ n * (n : ℂ) ^ (z - 1) / Complex.Gamma z *
          ∑' a : ℕ, B z a / (q : ℂ) ^ a‖ ≤ K * q ^ n * (n : ℝ) ^ (z.re - 2)
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 10.

TheoremSelberg–Delange theorem, \(h\)-th power version#●ready to prove

Let \(q > 1\) and \(A > 0\) be real numbers, let \(h \ge 1\) be an integer, let \(\xi\) be a primitive \(h\)-th root of unity in \(\mathbb{C}\), and let \(B_z(n)\) and \(C_z(n)\) be complex numbers, for \(z \in \mathbb{C}\) and integers \(n \ge 0\), such that for all \(z\) and \(n\)

\[C_z(n) = \sum_{\substack{0 \le a \le n \\ h \mid n - a}} B_z(a)\, q^{(n-a)/h} \frac{(z)_{(n-a)/h}}{((n-a)/h)!},\]

where \((z)_m = z(z+1)\cdots(z+m-1)\) is the rising factorial. Suppose there is a constant \(M\) such that for every complex \(z\) with \(|z| \le A\) the series \(\sum_{n \ge 0} |B_z(n)| (n+1)^{2A+2} q^{-n/h}\) converges and its sum is at most \(M\). Then there is a constant \(K\) such that for every complex \(z\) with \(|z| \le A\) and every integer \(n \ge 1\),

\[\left| C_z(n) - \frac{q^{n/h} n^{z-1}}{h^z \Gamma(z)} \sum_{j=0}^{h-1} \xi^{jn} \sum_{a \ge 0} B_z(a) \left(q^{1/h} \xi^j\right)^{-a} \right| \le K q^{n/h} n^{\operatorname{Re} z - 2}.\]

In terms of the generating functions \(B(u, z) = \sum_{n \ge 0} B_z(n) u^n\) and \(C(u, z) = \sum_{n \ge 0} C_z(n) u^n\), and with \(Z_q(u) = (1 - qu)^{-1}\), the hypothesis on \(C_z(n)\) says \(C(u, z) = B(u, z) Z_q(u^h)^z\), and the inner sums are \(B((q^{1/h} \xi^j)^{-1}, z)\). The paper's \(q\) is the size of the field. As in the case \(h = 1\), the weight is \((n+1)^{2A+2}\) rather than \(n^{2A+2}\), so that \(B_z(0)\) is bounded uniformly.

MetaMathlibExt.selbergDelange_functionField_pow · 15 lines
public theorem_wanted selbergDelange_functionField_pow
    (q : ℝ) (hq : 1 < q) (h : ℕ) (hh : 1 ≤ h) (ξ : ℂ) (hξ : IsPrimitiveRoot ξ h)
    (A : ℝ) (hA : 0 < A) (B Cz : ℂ → ℕ → ℂ)
    (hC : ∀ z n, Cz z n = ∑ a ∈ (Finset.range (n + 1)).filter (fun a => h ∣ n - a),
      B z a * (q : ℂ) ^ ((n - a) / h) * (ascPochhammer ℂ ((n - a) / h)).eval z /
        (((n - a) / h).factorial : ℂ))
    (hB : ∃ M : ℝ, ∀ z : ℂ, ‖z‖ ≤ A →
      Summable (fun n : ℕ => ‖B z n‖ * ((n : ℝ) + 1) ^ (2 * A + 2) / q ^ ((n : ℝ) / h)) ∧
        ∑' n : ℕ, ‖B z n‖ * ((n : ℝ) + 1) ^ (2 * A + 2) / q ^ ((n : ℝ) / h) ≤ M) :
    ∃ K : ℝ, ∀ z : ℂ, ‖z‖ ≤ A → ∀ n : ℕ, 1 ≤ n →
      ‖Cz z n - ((q ^ ((n : ℝ) / h) : ℝ) : ℂ) * (n : ℂ) ^ (z - 1) /
          ((h : ℂ) ^ z * Complex.Gamma z) *
          ∑ j ∈ Finset.range h, ξ ^ (j * n) *
            ∑' a : ℕ, B z a * (((q ^ ((1 : ℝ) / h) : ℝ) : ℂ) * ξ ^ j)⁻¹ ^ a‖
        ≤ K * q ^ ((n : ℝ) / h) * (n : ℝ) ^ (z.re - 2)
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 11.

DefinitionCoefficients of \(B_{1,S_h}(u, z)\)#✓fully proved

Let \(F\) be a finite field with \(q\) elements, let \(h\) be a natural number and let \(z\) be a complex number. Let \(S_h\) be the set of \(h\)-free monic polynomials over \(F\) (those divisible by no \(P^h\) with \(P\) monic irreducible), and \(\omega_1(f)\) the number of distinct monic irreducible factors of \(f\) of multiplicity exactly \(1\). Write \(C_{1,S_h}(u, z) = \sum_{f \in S_h} z^{\omega_1(f)} u^{\deg f}\) and \(B_{1,S_h}(u, z) = Z_q(u)^{-z} C_{1,S_h}(u, z)\), where \(Z_q(u)^{-z} = (1 - qu)^z\) is the power series with coefficient \(q^m (-z)_m / m!\) at \(u^m\) and \((x)_m = x(x+1) \cdots (x+m-1)\) is the rising factorial. For a natural number \(n\), \(B_z(n)\) is the coefficient of \(u^n\) in \(B_{1,S_h}(u, z)\), that is,

\[B_z(n) = \sum_{a=0}^{n} \Bigl(\sum_{f \in S_h,\ \deg f = a} z^{\omega_1(f)}\Bigr) \frac{q^{n-a} (-z)_{n-a}}{(n-a)!}.\]
public noncomputable def hFreeOmegaOneB (F : Type*) [Field F] [Fintype F] [DecidableEq F]
    (h : ℕ) (z : ℂ) (n : ℕ) : ℂ :=
  ∑ a ∈ Finset.range (n + 1),
    (∑ f ∈ (fixedDegreeMonic F a).filter (· ∈ hFree F h), z ^ omegaMult F 1 f) *
      (Fintype.card F : ℂ) ^ (n - a) * (ascPochhammer ℂ (n - a)).eval (-z) /
        ((n - a).factorial : ℂ)
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Section 3.1 (definition preceding Lemma 2).
Uses 3 · Used by 2

TheoremConstant coefficient of \(B_{1,S_h}\)#✓fully proved

Let \(F\) be a finite field with \(q\) elements and let \(h \ge 1\) be a natural number. Let \(S_h\) be the set of \(h\)-free monic polynomials over \(F\) (those divisible by no \(P^h\) with \(P\) monic irreducible) and \(\omega_1(f)\) the number of distinct monic irreducible factors of \(f\) of multiplicity exactly \(1\). For every complex number \(z\), the coefficient \(B_z(0)\) of \(u^0\) in the formal power series

\[B_{1,S_h}(u, z) = (1 - qu)^z \sum_{f \in S_h} z^{\omega_1(f)} u^{\deg f},\]

where \((1 - qu)^z = \sum_{m \ge 0} \binom{z}{m} (-qu)^m\), equals \(1\).

The only monic polynomial of degree \(0\) is \(1\), which is \(h\)-free and has \(\omega_1(1) = 0\).

public theorem hFreeOmegaOneB_zero (F : Type*) [Field F] [Fintype F] [DecidableEq F]
    (h : ℕ) (hh : 0 < h) (z : ℂ) : hFreeOmegaOneB F h z 0 = 1
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Section 3.1 (definition preceding Lemma 2).
Uses 7

DefinitionThe coefficients \(B_z(n)\) of the \(h\)-full series#✓fully proved

Let \(F\) be a finite field with \(q\) elements, let \(h\) and \(n\) be natural numbers and let \(z\) be a complex number. Write \(N_h\) for the set of \(h\)-full monic polynomials over \(F\) (monic \(f\) such that \(P^h\) divides \(f\) for every monic irreducible \(P\) dividing \(f\)), \(\omega_h(f)\) for the number of monic irreducible polynomials that divide \(f\) with multiplicity exactly \(h\), and \((x)_m = x(x + 1) \cdots (x + m - 1)\) for the rising factorial. For \(0 \le a \le n\) let \(c_a = \sum_f z^{\omega_h(f)}\), the sum over the \(f \in N_h\) of degree \(a\). Then \(B_z(n)\) is the sum of \(c_a \, q^m (-z)_m / m!\) over the \(a\) with \(0 \le a \le n\) and \(h \mid n - a\), where \(m = (n - a)/h\); when \(h = 0\) only \(a = n\) occurs, with \(m = 0\).

For \(h \ge 1\), \(B_z(n)\) is the coefficient of \(u^n\) in \(B_{h,N_h}(u, z) = (1 - qu^h)^z \sum_{f \in N_h} z^{\omega_h(f)} u^{\deg f}\), since \((1 - qu^h)^z\) has coefficient \(q^m (-z)_m / m!\) at \(u^{hm}\).

public noncomputable def hFullOmegaHB (F : Type*) [Field F] [Fintype F] [DecidableEq F]
    (h : ℕ) (z : ℂ) (n : ℕ) : ℂ :=
  ∑ a ∈ (Finset.range (n + 1)).filter (fun a => h ∣ n - a),
    (∑ f ∈ (fixedDegreeMonic F a).filter (· ∈ hFull F h), z ^ omegaMult F h f) *
      (Fintype.card F : ℂ) ^ ((n - a) / h) * (ascPochhammer ℂ ((n - a) / h)).eval (-z) /
        (((n - a) / h).factorial : ℂ)
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Section 4.1 (definition preceding Lemma 4).
Uses 3 · Used by 2

TheoremConstant coefficient of \(B_{h,N_h}\)#✓fully proved

Let \(F\) be a finite field with \(q\) elements, let \(h\) be a natural number and let \(z\) be a complex number. Then the coefficient \(B_z(0)\) of the \(h\)-full series for \(F\), \(h\) and \(z\) equals \(1\). For \(h \ge 1\), \(B_z(0)\) is the constant coefficient of \(B_{h,N_h}(u, z) = (1 - qu^h)^z \sum_{f \in N_h} z^{\omega_h(f)} u^{\deg f}\), where \(N_h\) is the set of \(h\)-full monic polynomials over \(F\) and \(\omega_h(f)\) is the number of monic irreducible polynomials dividing \(f\) with multiplicity exactly \(h\).

The only monic polynomial of degree \(0\) is \(1\), which is \(h\)-full and has \(\omega_h(1) = 0\).

public theorem hFullOmegaHB_zero (F : Type*) [Field F] [Fintype F] [DecidableEq F]
    (h : ℕ) (z : ℂ) : hFullOmegaHB F h z 0 = 1
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Section 4.1 (definition preceding Lemma 4).
Uses 7

TheoremWeighted coefficient bound for \(B_{1,S_h}\)#●ready to prove

Let \(F\) be a finite field with \(q\) elements, let \(h \ge 2\) be a natural number, and let \(A\) and \(\sigma > 1/2\) be real numbers. Let \(S_h\) be the set of \(h\)-free monic polynomials over \(F\) (those divisible by no \(P^h\) with \(P\) monic irreducible) and \(\omega_1(f)\) the number of distinct monic irreducible factors of \(f\) of multiplicity exactly \(1\). For a complex number \(z\) and a natural number \(a\) let \(B_z(a)\) be the coefficient of \(u^a\) in the formal power series

\[B_{1,S_h}(u, z) = (1 - qu)^z \sum_{f \in S_h} z^{\omega_1(f)} u^{\deg f},\]

where \((1 - qu)^z = \sum_{m \ge 0} \binom{z}{m} (-qu)^m\). Then there is a real constant \(c\) such that for every complex number \(z\) with \(|z| \le A\) and every natural number \(n \ge 2\),

\[\sum_{a=0}^{n} |B_z(a)|\, q^{-\sigma a} \le c.\]
public theorem_wanted hFreeOmegaOneB_weighted_sum_bounded
    (F : Type*) [Field F] [Fintype F] [DecidableEq F] (h : ℕ) (hh : 2 ≤ h) (A σ : ℝ)
    (hσ : 1 / 2 < σ) :
    ∃ c : ℝ, ∀ z : ℂ, ‖z‖ ≤ A → ∀ n : ℕ, 2 ≤ n →
      ∑ a ∈ Finset.range (n + 1),
        ‖hFreeOmegaOneB F h z a‖ / (Fintype.card F : ℝ) ^ (σ * a) ≤ c
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Lemma 2.
Uses 1

TheoremUniform bound for the weighted coefficients of \(B_{h,N_h}(u, z)\)#●ready to prove

Let \(F\) be a finite field with \(q\) elements, let \(h \ge 2\) be a natural number, and let \(A\) and \(\sigma\) be real numbers with \(\sigma > 1/(h + 1)\). Then there is a real constant \(c\) such that for every complex number \(z\) with \(|z| \le A\) and every natural number \(n \ge 2\),

\[\sum_{a=0}^{n} |B_z(a)| \, q^{-\sigma a} \le c,\]

where \(B_z(a)\) is the coefficient of \(u^a\) in the series \(B_{h,N_h}(u, z)\) attached to the \(h\)-full polynomials over \(F\).

public theorem_wanted hFullOmegaHB_weighted_sum_bounded
    (F : Type*) [Field F] [Fintype F] [DecidableEq F] (h : ℕ) (hh : 2 ≤ h) (A σ : ℝ)
    (hσ : 1 / ((h : ℝ) + 1) < σ) :
    ∃ c : ℝ, ∀ z : ℂ, ‖z‖ ≤ A → ∀ n : ℕ, 2 ≤ n →
      ∑ a ∈ Finset.range (n + 1),
        ‖hFullOmegaHB F h z a‖ / (Fintype.card F : ℝ) ^ (σ * a) ≤ c
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Lemma 4.
Uses 1

DefinitionThe pole parameter \(q^{1/h}\xi^j\)#✓fully proved

Let \(F\) be a finite set with \(q\) elements, and let \(h, j \in \mathbb{N}\) and \(\xi \in \mathbb{C}\). The pole parameter is the complex number \(q^{1/h}\xi^j\), where \(q^{1/h}\) is the nonnegative real \(h\)-th root of \(q\) (for \(h = 0\) the exponent \(1/h\) is read as \(0\), so that \(q^{1/h} = 1\)).

When \(F\) is a field, \(h \ge 1\) and \(\xi\) is a primitive \(h\)-th root of unity, the inverses \((q^{1/h}\xi^j)^{-1}\) are the poles \(u\) of \(Z_q(u^h)\), where \(Z_q(u) = 1/(1 - qu)\).

public noncomputable def hFullRoot (F : Type*) [Fintype F] (h : ℕ) (ξ : ℂ) (j : ℕ) : ℂ :=
  (((Fintype.card F : ℝ) ^ ((1 : ℝ) / h) : ℝ) : ℂ) * ξ ^ j
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Section 4.
Used by 11

TheoremFormula for the pole parameter#✓fully proved

Let \(F\) be a finite set with \(q\) elements, and let \(h, j \in \mathbb{N}\) and \(\xi \in \mathbb{C}\). The pole parameter \(q^{1/h}\xi^j\) equals the real power \(q^{1/h}\), whose exponent is the real number \(1/h\) (read as \(0\) when \(h = 0\)), viewed as a complex number and multiplied by \(\xi^j\).

public theorem hFullRoot_eq (F : Type*) [Fintype F] (h : ℕ) (ξ : ℂ) (j : ℕ) :
    hFullRoot F h ξ j = (((Fintype.card F : ℝ) ^ ((1 : ℝ) / h) : ℝ) : ℂ) * ξ ^ j
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Section 4.
Uses 1

DefinitionThe Euler product \(H_{N_h, S_\ell}\) for \(h\)-full, \(\ell\)-free polynomials#✓fully proved

Let \(F\) be a finite field, let \(h\) and \(\ell\) be natural numbers and let \(u\) be a complex number. Then \(H_{N_h, S_\ell}(u)\) is the complex number

\[H_{N_h, S_\ell}(u) = \prod_P (1 + \frac{x^{h+1} - x^{\ell} - x^{2h} + x^{h+\ell}}{1 - x}),\]

the product running over all monic irreducible polynomials \(P\) over \(F\), where \(x = u^{\deg P}\) in the factor for \(P\) (Equation (53)), the quotient is read as \(0\) when \(x = 1\), and the product is taken to be \(1\) if it does not converge unconditionally.

public noncomputable def hFullFreeEulerH (F : Type*) [Field F] [Fintype F] (h ℓ : ℕ) (u : ℂ) :
    ℂ :=
  ∏' P : monicIrreducible F,
    (1 + ((u ^ (P : Polynomial F).natDegree) ^ (h + 1) - (u ^ (P : Polynomial F).natDegree) ^ ℓ -
        (u ^ (P : Polynomial F).natDegree) ^ (2 * h) +
        (u ^ (P : Polynomial F).natDegree) ^ (h + ℓ)) / (1 - u ^ (P : Polynomial F).natDegree))
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Lemma 5, Equation (53).
Uses 1 · Used by 3

TheoremUnfolding the Euler product \(H_{N_h, S_\ell}\)#✓fully proved

Let \(F\) be a finite field, let \(h\) and \(\ell\) be natural numbers and let \(u\) be a complex number. Then \(H_{N_h, S_\ell}(u)\) equals the complex product over all monic irreducible polynomials \(P\) over \(F\)

\[\prod_P \Bigl(1 + \frac{x^{h+1} - x^{\ell} - x^{2h} + x^{h+\ell}}{1 - x}\Bigr),\]

where \(x = u^{\deg P}\) in the factor for \(P\), the quotient is read as \(0\) when \(x = 1\), and the product is taken to be \(1\) if it does not converge unconditionally.

public theorem hFullFreeEulerH_eq (F : Type*) [Field F] [Fintype F] (h ℓ : ℕ) (u : ℂ) :
    hFullFreeEulerH F h ℓ u = ∏' P : monicIrreducible F,
      (1 + ((u ^ (P : Polynomial F).natDegree) ^ (h + 1) - (u ^ (P : Polynomial F).natDegree) ^ ℓ -
          (u ^ (P : Polynomial F).natDegree) ^ (2 * h) +
          (u ^ (P : Polynomial F).natDegree) ^ (h + ℓ)) /
        (1 - u ^ (P : Polynomial F).natDegree))
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Lemma 5, Equation (53).
Uses 2

TheoremCounting \(h\)-full, \(\ell\)-free polynomials#●ready to prove

Let \(F\) be a finite field with \(q\) elements, let \(h\) and \(\ell\) be natural numbers with \(0 < h < \ell\), let \(\xi \in \mathbb{C}\) be a primitive \(h\)-th root of unity and let \(\varepsilon > 0\). A monic polynomial \(f\) over \(F\) is \(h\)-full if \(P^h \mid f\) for every monic irreducible \(P\) dividing \(f\), and \(\ell\)-free if \(P^\ell \nmid f\) for every monic irreducible \(P\). Write \(r_j = q^{1/h} \xi^j\) with \(q^{1/h}\) the positive real root, and let \(H(u)\) be the product over all monic irreducible \(P\) over \(F\) of \(1 + (x^{h+1} - x^\ell - x^{2h} + x^{h+\ell})/(1 - x)\), where \(x = u^{\deg P}\). Then there is a constant \(C\) such that for every \(n \ge \ell\) the number \(N\) of monic polynomials of degree \(n\) over \(F\) that are \(h\)-full and \(\ell\)-free satisfies

\[\Bigl| N - \frac{q^{n/h}}{h} \sum_{j=0}^{h-1} \xi^{jn} H(r_j^{-1}) \Bigr| \le C q^{n/(h+1) + \varepsilon n}.\]
public theorem_wanted card_hFull_hFree_asymptotic
    (F : Type*) [Field F] [Fintype F] [DecidableEq F] (h ℓ : ℕ) (hh : 0 < h) (hhℓ : h < ℓ)
    (ξ : ℂ) (hξ : IsPrimitiveRoot ξ h) (ε : ℝ) (hε : 0 < ε) :
    ∃ C : ℝ, ∀ n : ℕ, ℓ ≤ n →
      ‖((((fixedDegreeMonic F n).filter fun f => f ∈ hFull F h ∧ f ∈ hFree F ℓ).card : ℂ)) -
          (((Fintype.card F : ℝ) ^ ((n : ℝ) / h) / h : ℝ) : ℂ) *
            ∑ j ∈ Finset.range h, ξ ^ (j * n) * hFullFreeEulerH F h ℓ (hFullRoot F h ξ j)⁻¹‖ ≤
        C * (Fintype.card F : ℝ) ^ ((n : ℝ) / (h + 1) + ε * n)
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Lemma 5, Equation (51).
Uses 5

TheoremCounting \(h\)-full, \(\ell\)-free polynomials coprime to an irreducible#●ready to prove

Let \(F\) be a finite field with \(q\) elements, let \(h\) and \(\ell\) be natural numbers with \(0 < h < \ell\), let \(\xi \in \mathbb{C}\) be a primitive \(h\)-th root of unity, let \(P_0\) be a monic irreducible polynomial over \(F\) and let \(\varepsilon > 0\). A monic polynomial \(f\) over \(F\) is \(h\)-full if \(P^h \mid f\) for every monic irreducible \(P\) dividing \(f\), and \(\ell\)-free if \(P^\ell \nmid f\) for every monic irreducible \(P\). Write \(r_j = q^{1/h} \xi^j\) with \(q^{1/h}\) the positive real root, \(y_j = r_j^{-\deg P_0}\), and let \(H(u)\) be the product over all monic irreducible \(P\) over \(F\) of \(1 + (x^{h+1} - x^\ell - x^{2h} + x^{h+\ell})/(1 - x)\), where \(x = u^{\deg P}\). Then there is a constant \(C\) (which may depend on \(P_0\)) such that for every \(n \ge \ell\) the number \(N\) of monic polynomials of degree \(n\) over \(F\) that are \(h\)-full, \(\ell\)-free and coprime to \(P_0\) satisfies

\[\Bigl| N - \frac{q^{n/h}}{h} \sum_{j=0}^{h-1} \xi^{jn} H(r_j^{-1}) \frac{1 - y_j}{1 - y_j + y_j^h - y_j^\ell} \Bigr| \le C q^{n/(h+1) + \varepsilon n}.\]
public theorem_wanted card_hFull_hFree_coprime_asymptotic
    (F : Type*) [Field F] [Fintype F] [DecidableEq F] (h ℓ : ℕ) (hh : 0 < h) (hhℓ : h < ℓ)
    (ξ : ℂ) (hξ : IsPrimitiveRoot ξ h) (P₀ : Polynomial F) (hP₀ : P₀ ∈ monicIrreducible F)
    (ε : ℝ) (hε : 0 < ε) :
    ∃ C : ℝ, ∀ n : ℕ, ℓ ≤ n →
      ‖((((fixedDegreeMonic F n).filter fun f =>
            f ∈ hFull F h ∧ f ∈ hFree F ℓ ∧ IsCoprime f P₀).card : ℂ)) -
          (((Fintype.card F : ℝ) ^ ((n : ℝ) / h) / h : ℝ) : ℂ) *
            ∑ j ∈ Finset.range h, ξ ^ (j * n) * hFullFreeEulerH F h ℓ (hFullRoot F h ξ j)⁻¹ *
              ((1 - (hFullRoot F h ξ j)⁻¹ ^ P₀.natDegree) /
                (1 - (hFullRoot F h ξ j)⁻¹ ^ P₀.natDegree +
                  ((hFullRoot F h ξ j)⁻¹ ^ P₀.natDegree) ^ h -
                  ((hFullRoot F h ξ j)⁻¹ ^ P₀.natDegree) ^ ℓ))‖ ≤
        C * (Fintype.card F : ℝ) ^ ((n : ℝ) / (h + 1) + ε * n)
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Lemma 5, Equation (52).
Uses 6

DefinitionThe \(j\)-th moment of \(\omega_k\) over \(h\)-full polynomials of degree \(n\)#✓fully proved

Let \(F\) be a finite field and let \(h\), \(k\), \(j\) and \(n\) be natural numbers. Let \(N_h \cap M_n\) be the finite set of \(h\)-full monic polynomials of degree \(n\) over \(F\) (monic \(f\) such that \(P^h\) divides \(f\) for every monic irreducible \(P\) dividing \(f\)), and let \(\omega_k(f)\) be the number of monic irreducible polynomials that divide \(f\) with multiplicity exactly \(k\). The moment is the real number

\[|N_h \cap M_n|^{-1} \sum_{f \in N_h \cap M_n} \omega_k(f)^j,\]

taken to be \(0\) when \(N_h \cap M_n\) is empty.

public noncomputable def hFullMoment (F : Type*) [Field F] [Fintype F] [DecidableEq F]
    (h k j n : ℕ) : ℝ :=
  (∑ f ∈ (fixedDegreeMonic F n).filter (· ∈ hFull F h), (omegaMult F k f : ℝ) ^ j) /
    (((fixedDegreeMonic F n).filter (· ∈ hFull F h)).card : ℝ)
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorems 5 and 7.
Uses 3 · Used by 6

TheoremThe \(h\)-full moment is an average of \(\omega_k^j\)#✓fully proved

Let \(F\) be a finite field and let \(h\), \(k\), \(j\) and \(n\) be natural numbers. Let \(N_h \cap M_n\) be the finite set of \(h\)-full monic polynomials of degree \(n\) over \(F\) (monic \(f\) such that \(P^h\) divides \(f\) for every monic irreducible \(P\) dividing \(f\)), and let \(\omega_k(f)\) be the number of monic irreducible polynomials that divide \(f\) with multiplicity exactly \(k\). Then the \(j\)-th moment of \(\omega_k\) over \(N_h \cap M_n\) equals

\[|N_h \cap M_n|^{-1} \sum_{f \in N_h \cap M_n} \omega_k(f)^j,\]

where the quotient is \(0\) when \(N_h \cap M_n\) is empty. This holds by definition.

public theorem hFullMoment_eq (F : Type*) [Field F] [Fintype F] [DecidableEq F]
    (h k j n : ℕ) : hFullMoment F h k j n =
      (∑ f ∈ (fixedDegreeMonic F n).filter (· ∈ hFull F h), (omegaMult F k f : ℝ) ^ j) /
        (((fixedDegreeMonic F n).filter (· ∈ hFull F h)).card : ℝ)
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorems 5 and 7.
Uses 4

DefinitionThe local factor \(K(P, h, j)\)#✓fully proved

Let \(F\) be a finite field with \(q\) elements, let \(h\) and \(j\) be natural numbers, let \(\xi\) be a complex number and let \(P\) be a polynomial over \(F\). Write \(\rho_j = q^{1/h} \xi^j\), where \(q^{1/h}\) is the positive real \(h\)-th root of \(q\) (read as \(1\) when \(h = 0\)), and read \(\rho_j^{-1}\) as \(0\) when \(\rho_j = 0\); let \(|P| = q^{\deg P}\) if \(P \ne 0\) and \(|0| = 0\); and put \(y = (\rho_j^{-1})^{\deg P}\), with \(\deg 0\) read as \(0\). Then

\[K(P, h, j) = \frac{1 - y}{|P|\,(1 - y) + 1},\]

read as \(0\) when the denominator vanishes.

public noncomputable def hFullK (F : Type*) [Field F] [Fintype F] (h : ℕ) (ξ : ℂ) (j : ℕ)
    (P : Polynomial F) : ℂ :=
  (1 - (hFullRoot F h ξ j)⁻¹ ^ P.natDegree) /
    ((polyNorm F P : ℂ) * (1 - (hFullRoot F h ξ j)⁻¹ ^ P.natDegree) + 1)
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Section 1 (notation preceding Theorem 5).
Uses 2 · Used by 9

TheoremUnfolding the local factor \(K(P, h, j)\)#✓fully proved

Let \(F\) be a finite field with \(q\) elements, let \(h\) and \(j\) be natural numbers, let \(\xi\) be a complex number and let \(P\) be a polynomial over \(F\). Write \(\rho_j = q^{1/h} \xi^j\), where \(q^{1/h}\) is the positive real \(h\)-th root of \(q\) (read as \(1\) when \(h = 0\)), and read \(\rho_j^{-1}\) as \(0\) when \(\rho_j = 0\); let \(|P| = q^{\deg P}\) if \(P \ne 0\) and \(|0| = 0\); and put \(y = (\rho_j^{-1})^{\deg P}\), with \(\deg 0\) read as \(0\). Then \(K(P, h, j)\) equals

\[\frac{1 - y}{|P|\,(1 - y) + 1},\]

read as \(0\) when the denominator vanishes.

public theorem hFullK_eq (F : Type*) [Field F] [Fintype F] (h : ℕ) (ξ : ℂ) (j : ℕ)
    (P : Polynomial F) : hFullK F h ξ j P = (1 - (hFullRoot F h ξ j)⁻¹ ^ P.natDegree) /
      ((polyNorm F P : ℂ) * (1 - (hFullRoot F h ξ j)⁻¹ ^ P.natDegree) + 1)
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Section 1 (notation preceding Theorem 5).
Uses 3

DefinitionThe Euler product \(\Pi_j\) for \(h\)-full polynomials#✓fully proved

Let \(F\) be a finite field with \(q\) elements, let \(h\) and \(j\) be natural numbers and let \(\xi\) be a complex number. Write \(\rho_j = q^{1/h} \xi^j\), where \(q^{1/h}\) is the positive real \(h\)-th root of \(q\) (read as \(1\) when \(h = 0\)), read \(\rho_j^{-1}\) as \(0\) when \(\rho_j = 0\), and write \(|P| = q^{\deg P}\) for a monic irreducible polynomial \(P\) over \(F\). Then \(\Pi_j\) is the complex number

\[\Pi_j = \prod_P (1 - |P|^{-1})\Bigl(1 + \frac{1}{|P|\,(1 - (\rho_j^{-1})^{\deg P})}\Bigr),\]

the product running over all monic irreducible polynomials \(P\) over \(F\) (Equation (46)), where \(1/0\) is read as \(0\), and the product is taken to be \(1\) if it does not converge unconditionally.

public noncomputable def hFullEulerProduct (F : Type*) [Field F] [Fintype F] (h : ℕ) (ξ : ℂ)
    (j : ℕ) : ℂ :=
  ∏' P : monicIrreducible F, (1 - 1 / (polyNorm F P : ℂ)) *
    (1 + 1 / ((polyNorm F P : ℂ) * (1 - (hFullRoot F h ξ j)⁻¹ ^ (P : Polynomial F).natDegree)))
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Section 1 (asymptotic for |N_h ∩ M_n| preceding Theorem 5).
Uses 3 · Used by 3

TheoremUnfolding the Euler product \(\Pi_j\)#✓fully proved

Let \(F\) be a finite field with \(q\) elements, let \(h\) and \(j\) be natural numbers and let \(\xi\) be a complex number. Write \(\rho_j = q^{1/h} \xi^j\), where \(q^{1/h}\) is the positive real \(h\)-th root of \(q\) (read as \(1\) when \(h = 0\)), read \(\rho_j^{-1}\) as \(0\) when \(\rho_j = 0\), and write \(|P| = q^{\deg P}\) for a monic irreducible polynomial \(P\) over \(F\). Then \(\Pi_j\) equals the complex product over all monic irreducible polynomials \(P\) over \(F\)

\[\prod_P (1 - |P|^{-1})\Bigl(1 + \frac{1}{|P|\,(1 - (\rho_j^{-1})^{\deg P})}\Bigr),\]

where \(1/0\) is read as \(0\), and the product is taken to be \(1\) if it does not converge unconditionally.

public theorem hFullEulerProduct_eq (F : Type*) [Field F] [Fintype F] (h : ℕ) (ξ : ℂ)
    (j : ℕ) : hFullEulerProduct F h ξ j = ∏' P : monicIrreducible F,
      (1 - 1 / (polyNorm F P : ℂ)) *
        (1 + 1 / ((polyNorm F P : ℂ) *
          (1 - (hFullRoot F h ξ j)⁻¹ ^ (P : Polynomial F).natDegree)))
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Section 1 (asymptotic for |N_h ∩ M_n| preceding Theorem 5).
Uses 4

DefinitionThe \(h\)-full weighted mean#✓fully proved

Let \(F\) be a finite field with \(q\) elements, let \(h, n \in \mathbb{N}\), \(\xi \in \mathbb{C}\) and \(X : \mathbb{N} \to \mathbb{C}\). Let \(N_h \cap M_n\) be the set of \(h\)-full monic polynomials of degree \(n\) over \(F\). For each \(j\) let \(\rho_j = q^{1/h}\xi^j\) be the pole parameter and let \(\Pi_j = \prod_P (1 - 1/|P|)(1 + 1/(|P|(1 - \rho_j^{-\deg P})))\), the product over monic irreducible \(P\) with \(|P| = q^{\deg P}\), taken to be \(1\) when the family is not multipliable. The \(h\)-full weighted mean of \(X\) is the complex number

\[\frac{q^{n/h}/h}{|N_h \cap M_n|} \sum_{j=0}^{h-1} \xi^{jn} \, \Pi_j \, X_j.\]

Here \(q^{n/h}\) is a real power with real exponent \(n/h\), and division by zero (including \(0^{-1}\)) gives \(0\).

It carries every \(n\)-dependent constant in Theorems 5 and 7.

public noncomputable def hFullWeightedMean (F : Type*) [Field F] [Fintype F] [DecidableEq F]
    (h : ℕ) (ξ : ℂ) (n : ℕ) (X : ℕ → ℂ) : ℂ :=
  (((Fintype.card F : ℝ) ^ ((n : ℝ) / h) / h : ℝ) : ℂ) /
      (((fixedDegreeMonic F n).filter (· ∈ hFull F h)).card : ℂ) *
    ∑ j ∈ Finset.range h, ξ ^ (j * n) * hFullEulerProduct F h ξ j * X j
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorems 5 and 7.
Uses 3 · Used by 6

TheoremFormula for the \(h\)-full weighted mean#✓fully proved

Let \(F\) be a finite field with \(q\) elements, let \(h, n \in \mathbb{N}\), \(\xi \in \mathbb{C}\) and \(X : \mathbb{N} \to \mathbb{C}\). Let \(N_h \cap M_n\) be the set of \(h\)-full monic polynomials of degree \(n\) over \(F\). For each \(j\) let \(\rho_j = q^{1/h}\xi^j\) be the pole parameter and let \(\Pi_j = \prod_P (1 - 1/|P|)(1 + 1/(|P|(1 - \rho_j^{-\deg P})))\), the product over monic irreducible \(P\) with \(|P| = q^{\deg P}\), taken to be \(1\) when the family is not multipliable. Then the \(h\)-full weighted mean of \(X\) equals

\[\frac{q^{n/h}/h}{|N_h \cap M_n|} \sum_{j=0}^{h-1} \xi^{jn} \, \Pi_j \, X_j.\]

Here \(q^{n/h}\) is a real power with real exponent \(n/h\), and division by zero (including \(0^{-1}\)) gives \(0\).

public theorem hFullWeightedMean_eq (F : Type*) [Field F] [Fintype F] [DecidableEq F]
    (h : ℕ) (ξ : ℂ) (n : ℕ) (X : ℕ → ℂ) : hFullWeightedMean F h ξ n X =
      (((Fintype.card F : ℝ) ^ ((n : ℝ) / h) / h : ℝ) : ℂ) /
          (((fixedDegreeMonic F n).filter (· ∈ hFull F h)).card : ℂ) *
        ∑ j ∈ Finset.range h, ξ ^ (j * n) * hFullEulerProduct F h ξ j * X j
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorems 5 and 7.
Uses 4

DefinitionThe constant \(\kappa_j\) for \(h\)-full polynomials#✓fully proved

Let \(F\) be a finite field with \(q\) elements, let \(h\) and \(j\) be natural numbers and let \(\xi\) be a complex number. Write \(\rho = q^{1/h}\xi^j\), where \(q^{1/h}\) is the positive real \(h\)-th root of \(q\) for \(h \ge 1\) and \(q^{1/h} = 1\) for \(h = 0\), and let \(\rho^{-1}\) be read as \(0\) when \(\rho = 0\). For a monic irreducible polynomial \(P\) over \(F\) write \(|P| = q^{\deg P}\), \(y = (\rho^{-1})^{\deg P}\) and \(K(P, h, j) = (1 - y)/(|P|(1 - y) + 1)\), read as \(0\) when the denominator vanishes. Then \(\kappa_j = \sum_P (K(P, h, j) - 1/|P|)\), the sum over all monic irreducible polynomials \(P\) over \(F\), taken as an unconditional sum that is \(0\) when the family is not summable.

public noncomputable def hFullKSum (F : Type*) [Field F] [Fintype F] (h : ℕ) (ξ : ℂ)
    (j : ℕ) : ℂ :=
  ∑' P : monicIrreducible F, (hFullK F h ξ j P - 1 / (polyNorm F P : ℂ))
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 5.
Uses 3 · Used by 4

TheoremThe series defining \(\kappa_j\)#✓fully proved

Let \(F\) be a finite field with \(q\) elements, let \(h\) and \(j\) be natural numbers and let \(\xi\) be a complex number. Write \(\rho = q^{1/h}\xi^j\), where \(q^{1/h}\) is the positive real \(h\)-th root of \(q\) for \(h \ge 1\) and \(q^{1/h} = 1\) for \(h = 0\), and let \(\rho^{-1}\) be read as \(0\) when \(\rho = 0\). For a monic irreducible polynomial \(P\) over \(F\) write \(|P| = q^{\deg P}\), \(y = (\rho^{-1})^{\deg P}\) and \(K(P, h, j) = (1 - y)/(|P|(1 - y) + 1)\), read as \(0\) when the denominator vanishes. Then the constant \(\kappa_j\) attached to \(F\), \(h\), \(\xi\) and \(j\) equals \(\sum_P (K(P, h, j) - 1/|P|)\), the sum over all monic irreducible polynomials \(P\) over \(F\), taken as an unconditional sum that is \(0\) when the family is not summable. This holds by definition.

public theorem hFullKSum_eq (F : Type*) [Field F] [Fintype F] (h : ℕ) (ξ : ℂ) (j : ℕ) :
    hFullKSum F h ξ j =
      ∑' P : monicIrreducible F, (hFullK F h ξ j P - 1 / (polyNorm F P : ℂ))
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 5.
Uses 4

DefinitionThe sum \(\sum_P K(P, h, j)^2\) over monic irreducible polynomials#✓fully proved

Let \(F\) be a finite field with \(q\) elements, let \(h\) and \(j\) be natural numbers and let \(\xi\) be a complex number. Write \(\rho = q^{1/h}\xi^j\), where \(q^{1/h}\) is the positive real \(h\)-th root of \(q\) for \(h \ge 1\) and \(q^{1/h} = 1\) for \(h = 0\), and let \(\rho^{-1}\) be read as \(0\) when \(\rho = 0\). For a monic irreducible polynomial \(P\) over \(F\) write \(|P| = q^{\deg P}\), \(y = (\rho^{-1})^{\deg P}\) and \(K(P, h, j) = (1 - y)/(|P|(1 - y) + 1)\), read as \(0\) when the denominator vanishes. This defines the complex number \(\sum_P K(P, h, j)^2\), the sum over all monic irreducible polynomials \(P\) over \(F\), taken as an unconditional sum that is \(0\) when the family is not summable.

public noncomputable def hFullKSqSum (F : Type*) [Field F] [Fintype F] (h : ℕ) (ξ : ℂ)
    (j : ℕ) : ℂ :=
  ∑' P : monicIrreducible F, hFullK F h ξ j P ^ 2
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 5.
Uses 2 · Used by 3

TheoremUnfolding the sum of the squares \(K(P, h, j)^2\)#✓fully proved

Let \(F\) be a finite field, let \(h\) and \(j\) be natural numbers and let \(\xi\) be a complex number. The quantity \(\sum_P K(P, h, j)^2\) of Theorem 5 is the complex sum, over all monic irreducible polynomials \(P\) over \(F\), of the squares of the local factors \(K(P, h, j)\) attached to \(h\), \(j\) and \(\xi\), taken to be \(0\) if it does not converge absolutely.

public theorem hFullKSqSum_eq (F : Type*) [Field F] [Fintype F] (h : ℕ) (ξ : ℂ) (j : ℕ) :
    hFullKSqSum F h ξ j = ∑' P : monicIrreducible F, hFullK F h ξ j P ^ 2
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 5.
Uses 3

DefinitionThe \(h\)-full prime sum \(\sum_P b_P\)#✓fully proved

Let \(F\) be a finite field with \(q\) elements, let \(h, k, j \in \mathbb{N}\) and \(\xi \in \mathbb{C}\), and let \(\rho = q^{1/h}\xi^j\) be the pole parameter, where \(q^{1/h}\) is a real power whose exponent \(1/h\) is read as \(0\) when \(h = 0\). For a monic irreducible polynomial \(P\) over \(F\) put \(|P| = q^{\deg P}\), \(y_P = \rho^{-\deg P}\), \(K(P, h, j) = (1 - y_P)/(|P|(1 - y_P) + 1)\) and \(b_P = |P| \, y_P^{k} \, K(P, h, j)\). The \(h\)-full prime sum is the complex number \(\sum_P b_P\) over all monic irreducible \(P\), taken to be \(0\) when the family \((b_P)\) is not summable. Inverses use the convention \(0^{-1} = 0\).

public noncomputable def hFullOmegaMultSum (F : Type*) [Field F] [Fintype F] (h k : ℕ) (ξ : ℂ)
    (j : ℕ) : ℂ :=
  ∑' P : monicIrreducible F, (polyNorm F P : ℂ) *
    (hFullRoot F h ξ j)⁻¹ ^ (k * (P : Polynomial F).natDegree) * hFullK F h ξ j P
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 7.
Uses 4 · Used by 3

TheoremFormula for the \(h\)-full prime sum \(\sum_P b_P\)#✓fully proved

Let \(F\) be a finite field with \(q\) elements, let \(h, k, j \in \mathbb{N}\) and \(\xi \in \mathbb{C}\), and let \(\rho = q^{1/h}\xi^j\) be the pole parameter, where \(q^{1/h}\) is a real power whose exponent \(1/h\) is read as \(0\) when \(h = 0\). For a monic irreducible polynomial \(P\) over \(F\) put \(|P| = q^{\deg P}\), \(K(P, h, j) = (1 - \rho^{-\deg P})/(|P|(1 - \rho^{-\deg P}) + 1)\) and \(b_P = |P| \, (\rho^{-1})^{k \deg P} \, K(P, h, j)\). Then the \(h\)-full prime sum \(\sum_P b_P\) equals the sum of \(b_P\) over all monic irreducible polynomials \(P\) over \(F\), taken to be \(0\) when the family is not summable. Inverses use the convention \(0^{-1} = 0\).

public theorem hFullOmegaMultSum_eq (F : Type*) [Field F] [Fintype F] (h k : ℕ) (ξ : ℂ)
    (j : ℕ) : hFullOmegaMultSum F h k ξ j = ∑' P : monicIrreducible F, (polyNorm F P : ℂ) *
      (hFullRoot F h ξ j)⁻¹ ^ (k * (P : Polynomial F).natDegree) * hFullK F h ξ j P
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 7.
Uses 5

DefinitionThe sum \(\sum_P b_P^2\) over monic irreducible polynomials#✓fully proved

Let \(F\) be a finite field with \(q\) elements, let \(h\), \(k\) and \(j\) be natural numbers and let \(\xi\) be a complex number. Write \(\rho = q^{1/h}\xi^j\), where \(q^{1/h}\) is the positive real \(h\)-th root of \(q\) for \(h \ge 1\) and \(q^{1/h} = 1\) for \(h = 0\), and let \(\rho^{-1}\) be read as \(0\) when \(\rho = 0\). For a monic irreducible polynomial \(P\) over \(F\) write \(|P| = q^{\deg P}\), \(y = (\rho^{-1})^{\deg P}\), \(K(P, h, j) = (1 - y)/(|P|(1 - y) + 1)\), read as \(0\) when the denominator vanishes, and \(b_P = |P| (\rho^{-1})^{k \deg P} K(P, h, j)\). This defines the complex number \(\sum_P b_P^2\), the sum over all monic irreducible polynomials \(P\) over \(F\), taken as an unconditional sum that is \(0\) when the family is not summable.

public noncomputable def hFullOmegaMultSqSum (F : Type*) [Field F] [Fintype F] (h k : ℕ)
    (ξ : ℂ) (j : ℕ) : ℂ :=
  ∑' P : monicIrreducible F, ((polyNorm F P : ℂ) *
    (hFullRoot F h ξ j)⁻¹ ^ (k * (P : Polynomial F).natDegree) * hFullK F h ξ j P) ^ 2
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 7.
Uses 4 · Used by 2

TheoremThe series defining \(\sum_P b_P^2\)#✓fully proved

Let \(F\) be a finite field with \(q\) elements, let \(h\), \(k\) and \(j\) be natural numbers and let \(\xi\) be a complex number. Write \(\rho = q^{1/h}\xi^j\), where \(q^{1/h}\) is the positive real \(h\)-th root of \(q\) for \(h \ge 1\) and \(q^{1/h} = 1\) for \(h = 0\), and let \(\rho^{-1}\) be read as \(0\) when \(\rho = 0\). For a monic irreducible polynomial \(P\) over \(F\) write \(|P| = q^{\deg P}\), \(y = (\rho^{-1})^{\deg P}\) and \(K(P, h, j) = (1 - y)/(|P|(1 - y) + 1)\), read as \(0\) when the denominator vanishes. Then the constant \(\sum_P b_P^2\) attached to \(F\), \(h\), \(k\), \(\xi\) and \(j\) equals \(\sum_P (|P| (\rho^{-1})^{k \deg P} K(P, h, j))^2\), the sum over all monic irreducible polynomials \(P\) over \(F\), taken as an unconditional sum that is \(0\) when the family is not summable. This holds by definition.

public theorem hFullOmegaMultSqSum_eq (F : Type*) [Field F] [Fintype F] (h k : ℕ) (ξ : ℂ)
    (j : ℕ) : hFullOmegaMultSqSum F h k ξ j = ∑' P : monicIrreducible F, ((polyNorm F P : ℂ) *
      (hFullRoot F h ξ j)⁻¹ ^ (k * (P : Polynomial F).natDegree) * hFullK F h ξ j P) ^ 2
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 7.
Uses 5

TheoremMean of \(\omega_h\) over \(h\)-full polynomials#●ready to prove

Let \(F\) be a finite field with \(q\) elements, let \(h \ge 2\), let \(\xi \in \mathbb{C}\) be a primitive \(h\)-th root of unity, and let \(\varepsilon > 0\). Write \(N_h \cap M_n\) for the set of monic polynomials \(f\) of degree \(n\) over \(F\) that are \(h\)-full (if a monic irreducible \(P\) divides \(f\), then so does \(P^h\)), and \(\omega_h(f)\) for the number of monic irreducible \(P\) that divide \(f\) exactly \(h\) times. For monic irreducible \(P\) and \(j < h\) put \(|P| = q^{\deg P}\), \(y_{P,j} = (q^{1/h}\xi^j)^{-\deg P}\) with \(q^{1/h} > 0\), and \(K(P, h, j) = (1 - y_{P,j})/(|P|(1 - y_{P,j}) + 1)\). Let \(\kappa_j = \sum_P (K(P, h, j) - |P|^{-1})\) and \(\Pi_j = \prod_P (1 - |P|^{-1})(1 + |P|^{-1}(1 - y_{P,j})^{-1})\), with sum and product over monic irreducible \(P\), and for \(X = (X_j)_j\) put \(W_n(X) = |N_h \cap M_n|^{-1} (q^{n/h}/h) \sum_{j=0}^{h-1} \xi^{jn} \Pi_j X_j\). Let \(B_1\) be the function field Mertens constant and \(L_n = \log(n/h)\). Then, as \(n \to \infty\), the mean of \(\omega_h\) over \(N_h \cap M_n\) is \(L_n + B_1 + W_n(\kappa) + O(n^{\varepsilon - 1})\).

public theorem_wanted omegaH_hFull_mean_asymptotic
    (F : Type*) [Field F] [Fintype F] [DecidableEq F] (h : ℕ) (hh : 2 ≤ h) (ξ : ℂ)
    (hξ : IsPrimitiveRoot ξ h) (ε : ℝ) (hε : 0 < ε) :
    (fun n : ℕ => ((hFullMoment F h h 1 n : ℝ) : ℂ) -
        ((Real.log ((n : ℝ) / h) : ℂ) + (functionFieldMertensConstant F : ℂ) +
          hFullWeightedMean F h ξ n (hFullKSum F h ξ)))
      =O[atTop] (fun n : ℕ => (n : ℝ) ^ (ε - 1))
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 5, Equation (8).
Uses 4

TheoremSecond moment of \(\omega_h\) over \(h\)-full polynomials#●ready to prove

Let \(F\) be a finite field with \(q\) elements, let \(h \ge 2\), let \(\xi \in \mathbb{C}\) be a primitive \(h\)-th root of unity, and let \(\varepsilon > 0\). Write \(N_h \cap M_n\) for the set of monic polynomials \(f\) of degree \(n\) over \(F\) that are \(h\)-full (if a monic irreducible \(P\) divides \(f\), then so does \(P^h\)), and \(\omega_h(f)\) for the number of monic irreducible \(P\) that divide \(f\) exactly \(h\) times. For monic irreducible \(P\) and \(j < h\) put \(|P| = q^{\deg P}\), \(y_{P,j} = (q^{1/h}\xi^j)^{-\deg P}\) with \(q^{1/h} > 0\), and \(K(P, h, j) = (1 - y_{P,j})/(|P|(1 - y_{P,j}) + 1)\). Let \(\kappa_j = \sum_P (K(P, h, j) - |P|^{-1})\) and \(\Pi_j = \prod_P (1 - |P|^{-1})(1 + |P|^{-1}(1 - y_{P,j})^{-1})\), with sum and product over monic irreducible \(P\), and for \(X = (X_j)_j\) put \(W_n(X) = |N_h \cap M_n|^{-1} (q^{n/h}/h) \sum_{j=0}^{h-1} \xi^{jn} \Pi_j X_j\). Let \(B_1\) be the function field Mertens constant and \(L_n = \log(n/h)\). Then, as \(n \to \infty\), the mean of \(\omega_h^2\) over \(N_h \cap M_n\) is \(L_n^2 + (2B_1 + 1 + 2W_n(\kappa)) L_n + B_1^2 + B_1 - \pi^2/6 + W_n(X) + O(n^{\varepsilon - 1})\), where \(X_j = -\sum_P K(P, h, j)^2 + \kappa_j^2 + (2B_1 + 1)\kappa_j\).

This follows the paper's proof: the printed constant term \(C_3\) has \(-W_n(Z)\) in place of \(W_n(X)\), where \(Z_j = \sum_P K(P, h, j)^2 + \kappa_j^2 + (2B_1 + 1)\kappa_j\); this contradicts the final display of the proof (page 29) and the printed variance.

public theorem_wanted omegaH_hFull_secondMoment_asymptotic
    (F : Type*) [Field F] [Fintype F] [DecidableEq F] (h : ℕ) (hh : 2 ≤ h) (ξ : ℂ)
    (hξ : IsPrimitiveRoot ξ h) (ε : ℝ) (hε : 0 < ε) :
    (fun n : ℕ => ((hFullMoment F h h 2 n : ℝ) : ℂ) -
        ((Real.log ((n : ℝ) / h) : ℂ) ^ 2 +
          (2 * (functionFieldMertensConstant F : ℂ) + 1 +
            2 * hFullWeightedMean F h ξ n (hFullKSum F h ξ)) * (Real.log ((n : ℝ) / h) : ℂ) +
          ((functionFieldMertensConstant F : ℂ) ^ 2 + (functionFieldMertensConstant F : ℂ) -
              (Real.pi : ℂ) ^ 2 / 6 +
            hFullWeightedMean F h ξ n (fun j => -hFullKSqSum F h ξ j + hFullKSum F h ξ j ^ 2 +
              (2 * (functionFieldMertensConstant F : ℂ) + 1) * hFullKSum F h ξ j))))
      =O[atTop] (fun n : ℕ => (n : ℝ) ^ (ε - 1))
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 5, Equation (9).
Uses 5

TheoremVariance of \(\omega_h\) over \(h\)-full polynomials#●ready to prove

Let \(F\) be a finite field with \(q\) elements, let \(h \ge 2\), let \(\xi \in \mathbb{C}\) be a primitive \(h\)-th root of unity, and let \(\varepsilon > 0\). Write \(N_h \cap M_n\) for the set of monic polynomials \(f\) of degree \(n\) over \(F\) that are \(h\)-full (if a monic irreducible \(P\) divides \(f\), then so does \(P^h\)), and \(\omega_h(f)\) for the number of monic irreducible \(P\) that divide \(f\) exactly \(h\) times. For monic irreducible \(P\) and \(j < h\) put \(|P| = q^{\deg P}\), \(y_{P,j} = (q^{1/h}\xi^j)^{-\deg P}\) with \(q^{1/h} > 0\), and \(K(P, h, j) = (1 - y_{P,j})/(|P|(1 - y_{P,j}) + 1)\). Let \(\kappa_j = \sum_P (K(P, h, j) - |P|^{-1})\) and \(\Pi_j = \prod_P (1 - |P|^{-1})(1 + |P|^{-1}(1 - y_{P,j})^{-1})\), with sum and product over monic irreducible \(P\), and for \(X = (X_j)_j\) put \(W_n(X) = |N_h \cap M_n|^{-1} (q^{n/h}/h) \sum_{j=0}^{h-1} \xi^{jn} \Pi_j X_j\). Let \(B_1\) be the function field Mertens constant and \(L_n = \log(n/h)\). Then, as \(n \to \infty\), the variance of \(\omega_h\) over \(N_h \cap M_n\) (the mean of \(\omega_h^2\) minus the square of the mean of \(\omega_h\)) is \(L_n + B_1 - \pi^2/6 + W_n(Y) - W_n(\kappa)^2 + O(n^{\varepsilon - 1})\), where \(Y_j = -\sum_P K(P, h, j)^2 + \kappa_j^2 + \kappa_j\).

The printed display writes \(\omega_1\) for \(\omega_h\) in the definition of the variance and omits the factor \(q^{n/h}/h\) in both weighted sums; both are restored as in Equations (8) and (9), from which the paper derives the variance.

public theorem_wanted omegaH_hFull_variance_asymptotic
    (F : Type*) [Field F] [Fintype F] [DecidableEq F] (h : ℕ) (hh : 2 ≤ h) (ξ : ℂ)
    (hξ : IsPrimitiveRoot ξ h) (ε : ℝ) (hε : 0 < ε) :
    (fun n : ℕ => ((hFullMoment F h h 2 n - hFullMoment F h h 1 n ^ 2 : ℝ) : ℂ) -
        ((Real.log ((n : ℝ) / h) : ℂ) + (functionFieldMertensConstant F : ℂ) -
            (Real.pi : ℂ) ^ 2 / 6 +
          hFullWeightedMean F h ξ n
            (fun j => -hFullKSqSum F h ξ j + hFullKSum F h ξ j ^ 2 + hFullKSum F h ξ j) -
          hFullWeightedMean F h ξ n (hFullKSum F h ξ) ^ 2))
      =O[atTop] (fun n : ℕ => (n : ℝ) ^ (ε - 1))
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 5.
Uses 5

TheoremMean of \(\omega_k\) over \(h\)-full polynomials for \(k > h\)#●ready to prove

Let \(F\) be a finite field with \(q\) elements, let \(2 \le h < k\), let \(\xi \in \mathbb{C}\) be a primitive \(h\)-th root of unity and let \(\varepsilon > 0\). Write \(M_n\) for the set of monic polynomials of degree \(n\) over \(F\), \(N_h\) for the set of \(h\)-full monic polynomials, \(|P| = q^{\deg P}\), and \(\omega_k(f)\) for the number of monic irreducible \(P\) dividing \(f\) whose multiplicity in \(f\) is exactly \(k\). For \(j < h\) and a monic irreducible \(P\) put \(y_{P,j} = (q^{1/h}\xi^j)^{-\deg P}\), where \(q^{1/h}\) is the positive real root, \(K(P, h, j) = (1 - y_{P,j})/(|P|(1 - y_{P,j}) + 1)\) and \(b_P(j) = |P| (q^{1/h}\xi^j)^{-k \deg P} K(P, h, j)\), and let \(\Pi_j = \prod_P (1 - 1/|P|)(1 + 1/(|P|(1 - y_{P,j})))\), where sums and products over \(P\) run over the monic irreducible polynomials. For \(X = (X_0, \dots, X_{h-1}) \in \mathbb{C}^h\) let \(W_n(X) = |N_h \cap M_n|^{-1} (q^{n/h}/h) \sum_{j\lt h} \xi^{jn} \Pi_j X_j\). Then the mean of \(\omega_k\) over \(N_h \cap M_n\) equals \(W_n\bigl(\sum_P b_P(0), \dots, \sum_P b_P(h-1)\bigr) + O(q^{-n/(h(h+1)) + \varepsilon n})\) as \(n \to \infty\).

public theorem_wanted omegaMult_hFull_mean_asymptotic
    (F : Type*) [Field F] [Fintype F] [DecidableEq F] (h k : ℕ) (hh : 2 ≤ h) (hhk : h < k)
    (ξ : ℂ) (hξ : IsPrimitiveRoot ξ h) (ε : ℝ) (hε : 0 < ε) :
    (fun n : ℕ => ((hFullMoment F h k 1 n : ℝ) : ℂ) -
        hFullWeightedMean F h ξ n (hFullOmegaMultSum F h k ξ))
      =O[atTop] (fun n : ℕ =>
        (Fintype.card F : ℝ) ^ (-((n : ℝ) / (h * (h + 1))) + ε * n))
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 7.
Uses 3

TheoremSecond moment of \(\omega_k\) over \(h\)-full polynomials for \(k > h\)#●ready to prove

Let \(F\) be a finite field with \(q\) elements, let \(2 \le h < k\), let \(\xi \in \mathbb{C}\) be a primitive \(h\)-th root of unity and let \(\varepsilon > 0\). Write \(M_n\) for the set of monic polynomials of degree \(n\) over \(F\), \(N_h\) for the set of \(h\)-full monic polynomials, \(|P| = q^{\deg P}\), and \(\omega_k(f)\) for the number of monic irreducible \(P\) dividing \(f\) whose multiplicity in \(f\) is exactly \(k\). For \(j < h\) and a monic irreducible \(P\) put \(y_{P,j} = (q^{1/h}\xi^j)^{-\deg P}\), where \(q^{1/h}\) is the positive real root, \(K(P, h, j) = (1 - y_{P,j})/(|P|(1 - y_{P,j}) + 1)\) and \(b_P(j) = |P| (q^{1/h}\xi^j)^{-k \deg P} K(P, h, j)\), and let \(\Pi_j = \prod_P (1 - 1/|P|)(1 + 1/(|P|(1 - y_{P,j})))\), where sums and products over \(P\) run over the monic irreducible polynomials. For \(X = (X_0, \dots, X_{h-1}) \in \mathbb{C}^h\) let \(W_n(X) = |N_h \cap M_n|^{-1} (q^{n/h}/h) \sum_{j\lt h} \xi^{jn} \Pi_j X_j\). Then the mean of \(\omega_k^2\) over \(N_h \cap M_n\) equals \(W_n(X) + O(q^{-n/(h(h+1)) + \varepsilon n})\) as \(n \to \infty\), where \(X_j = (\sum_P b_P(j))^2 - \sum_P b_P(j)^2 + \sum_P b_P(j)\).

This is the reading of the paper's proof. The printed statement has \(\sum_P b_P^2 - (\sum_P b_P)^2\) (with \(b_P = b_P(j)\)) with the signs swapped, contradicting the computation of the second derivative in \(z\) of the paper's generating function \(B_{k,N_h}(u, z)\) at the end of the proof (page 31).

public theorem_wanted omegaMult_hFull_secondMoment_asymptotic
    (F : Type*) [Field F] [Fintype F] [DecidableEq F] (h k : ℕ) (hh : 2 ≤ h) (hhk : h < k)
    (ξ : ℂ) (hξ : IsPrimitiveRoot ξ h) (ε : ℝ) (hε : 0 < ε) :
    (fun n : ℕ => ((hFullMoment F h k 2 n : ℝ) : ℂ) -
        hFullWeightedMean F h ξ n (fun j => hFullOmegaMultSum F h k ξ j ^ 2 -
          hFullOmegaMultSqSum F h k ξ j + hFullOmegaMultSum F h k ξ j))
      =O[atTop] (fun n : ℕ =>
        (Fintype.card F : ℝ) ^ (-((n : ℝ) / (h * (h + 1))) + ε * n))
Sources
  • Juan Arévalo Gómez and Matilde Lalín, Prime Factors with Given Multiplicity in h-Free and h-Full Polynomials over Function Fields, INTEGERS 25 (2025), Article A9, Theorem 7.
Uses 4
55 fully proved23 ready to prove

The dependency explorer needs JavaScript and its graph data.

Download the complete graph data.