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@CoolRmal CoolRmal commented Jan 8, 2026

Closes #1543

van Doorn's constructions implies that there exists a set A such that lim sup |A ∩ {1, …, N}| / N^(1/2) ≤ (2 * (φ ^ (5 / 2))). Hence, the minimum value of limsup is less than (2 * (φ ^ (5 / 2))).

Also fixes some typos.

@github-actions github-actions bot added the erdos-problems Erdős Problems label Jan 8, 2026
@Paul-Lez Paul-Lez self-requested a review January 12, 2026 16:31
Comment on lines -44 to +45
theorem erdos_33 : IsLeast
{ c : EReal | ∃ (A : Set ℕ), AdditiveBasisCondition A ∧
Filter.atTop.limsup (fun N => (A.interIcc 1 N).ncard / √N) = c}
answer(sorry) := by
theorem erdos_33 : ⨅ A : {A : Set ℕ | AdditiveBasisCondition A}, Filter.atTop.limsup (fun N =>
(A.1.interIcc 1 N).ncard / (√N : EReal)) = answer(sorry) := by
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I'm not sure I understand this change. Can you explain?

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The infimum of a set s may not belong to that set, while IsLeast s ∈ s. Based on the problem description, I don't think we know that the infimum is attained by some element.

@YaelDillies YaelDillies added the awaiting-author The author should answer a question or perform changes. Reply when done. label Jan 17, 2026
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Erdős Problem #33: sup/inf confusion?

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