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Erdős problem 379

Let S(n)S(n) denote the largest integer such that, for all 1≤k<n1 ≤ k < n, the binomial coefficient (nk)\binom{n}{k} is divisible by pS(n)p^S(n) for some prime pp (depending on kk).Then lim sup⁡S(n)=∞\limsup S(n) = \infty.

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1 retained statement36c6d0fef71a

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FormalConjectures/ErdosProblems/

379.lean

Retained formal statement1 of 1

Let S(n)S(n) denote the largest integer such that, for all 1≤k<n1 ≤ k < n, the binomial coefficient (nk)\binom{n}{k} is divisible by pS(n)p^S(n) for some prime pp (depending on kk).Then lim sup⁡S(n)=∞\limsup S(n) = \infty.

This was formalized in Lean by Tao.

FormalConjectures/ErdosProblems/379.leanErdos379.erdos_3791 lineExact file
Filter.limsup (fun n => ↑(Erdos379.S n)) Filter.atTop = ⊤
SolvedProof has a holelean4external proof

The proof uses `sorry`: part of the argument is written but not proved. Lean accepts the file; it does not accept the theorem.