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Erdős problem 400 - part i · Conjectures.io
week of 11 Oct 2025 · nothing published week of 18 Oct 2025 · nothing published week of 25 Oct 2025 · nothing published week of 1 Nov 2025 · nothing published week of 8 Nov 2025 · nothing published week of 15 Nov 2025 · nothing published
Solve it Nobody has attempted this. A complete proof or refutation takes the whole bounty.
Add the first piece Even one lemma helps. Whoever finishes this later shares the pool with everyone who got them there.
contrib new erdos-400-parts-iCommand line, then a pull request on GitHub.
← Erdős problem 398 Erdős problem 406 - one two →
What has been built Nothing has been published against this problem yet.
A first lemma is worth as much as a last one: whoever closes the problem shares the pool with everyone who got them there.
Proof target
import FormalConjectures.ErdosProblems.«400»
import TaskSupport
namespace Bounty
theorem target : fcTypeOfName% "Erdos400.erdos_400.parts.i" := by
sorry
end Bounty
Open this target’s Challenge.lean Original conjecture (Lean type)
True ↔
∀ k ≥ 2,
∃ c,
Asymptotics.IsEquivalent Filter.atTop (fun x => ∑ n ∈ Finset.Icc 1 x, ↑(Erdos400.g k n)) fun x =>
c * ↑x * Real.log ↑xOriginal conjecture source: FormalConjectures/ErdosProblems/400.lean
Source type SHA-256 sha256:71d81fb5ece337687bd6c52418ef242d0b0b2c6004532cea871d437abe64b2a6
Task id fc-6a786f99-parts-i-543a783dff-formalized-v1
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11 Oct 2025 nothing published against this one yet 3 Oct 2026
erdosproblems.com/400
Something wrong with this formalization?
A statement that does not faithfully capture the original conjecture is the one real risk here, so we would rather hear about it early - before someone spends weeks on it.
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Reward
0 α
for closing this problem
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