Skip to content

Conversation

@seewoo5
Copy link
Contributor

@seewoo5 seewoo5 commented Sep 26, 2025

There might be a better way to deal with nonnegative irreducible polynomials, and feel free to give a comment on it.

@Paul-Lez Paul-Lez self-requested a review September 29, 2025 12:47
Copy link
Member

@Paul-Lez Paul-Lez left a comment

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Thanks for the PR! A few very small comments - I'll take another look later on

@Paul-Lez Paul-Lez self-requested a review October 16, 2025 09:43
Comment on lines +46 to +48
/- Auxiliary definition for nonnegative irreducible polynomials over $\mathbb{Z}$ on $\mathbb{N}$. -/
def Erdos975NonnegIrredPoly (f : ℕ → ℕ) (g : ℤ[X]) : Prop :=
Irreducible g ∧ ∃ N : ℕ, ∀ n ≥ N, f n = g.eval ↑n ∧ 0 ≤ f n
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I would be tempted to remove this condition, and just do everything in terms of the polynomial g (and g.eval when you want to use the corresponding function!)

Comment on lines +53 to +61
/--
For an irreducible polynomial $f \in \mathbb{Z}[x]$ with $f(n) \ge 1$ for sufficiently large $n$,
does there exists a constant $c = c(f) > 0$ such that
$\sum_{n \le x} \tau(f(n)) \approx c \cdot x \log x$?
-/
@[category research open, AMS 11]
theorem erdos_975 (f : ℕ → ℕ) (g : ℤ[X]) (hf : Erdos975NonnegIrredPoly f g) :
(∃ (c : ℝ), 0 < c ∧ Erdos975Asymptotic f c) ↔ answer(sorry) := by
sorry
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Here, I would recommend moving the quantification "inside". That way, replacing sorry by false will correspond to the negation of the statement.

@[category research solved, AMS 11]
theorem erdos_975.variant.quadratic (f : ℕ → ℕ) (g : ℤ[X]) (hf : Erdos975NonnegIrredPoly f g)
(hg_degree : g.degree = 2) :
∃ (c : ℝ), 0 < c ∧ Erdos975Asymptotic f c := by
Copy link
Member

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Here you could possibly use answer(sorry) as a placeholder for c (and then later replace sorry by the actual closed form!)

Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment

Projects

None yet

Development

Successfully merging this pull request may close these issues.

3 participants