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Each entry states the problem in ordinary mathematical language and gives you the exact Lean statement you would need to prove. Nothing is paraphrased, so what you read is what gets checked.
Number theory
Withdrawn
Erdős problem 536
Let ϵ>0 and N be sufficiently large. Is it true that if A⊆{1,…,N}
has
size at least
ϵN
then there must be distinct
a,b,c∈A
such that
[a,b]=[b,c]=[a,c],
where
[⋅,⋅]
denotes the least common multiple?
Withdrawn 19 Aug 2026
WITHDRAWN (removed from the active solver pool by maintainer request)
True ↔
∀ ε > 0,
∀ᶠ (N : ℕ) in Filter.atTop,
∀ A ⊆ Finset.Icc 1 N,
ε * ↑N ≤ ↑A.card → ∃ a ∈ A, ∃ b ∈ A, ∃ c ∈ A, {a, b, c}.card = 3 ∧ a.lcm b = b.lcm c ∧ b.lcm c = a.lcm c
What you must prove
import FormalConjectures.ErdosProblems.«536»
import TaskSupport
namespace Bounty
theorem target : fcTypeOfName% "Erdos536.erdos_536" := by
sorry
end Bounty
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.