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Erdős problem 376

Are there infinitely many nn such that (2nn){2n\choose n} is coprime to 105105?

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FormalConjectures/ErdosProblems/

376.lean

Retained formal statement2 of 2

Erdős, Graham, Ruzsa, and Straus [EGRS75] have shown that, for any two odd primes pp and qq, there are infinite many nn such that (2nn){2n\choose n} is coprime to pqpq.

FormalConjectures/ErdosProblems/376.leanErdos376.erdos_376.variants.prime1 lineExact file
∀ {p q : ℕ}, Nat.Prime p → Odd p → Nat.Prime q → Odd q → {n | n.centralBinom.Coprime (p * q)}.Infinite
SolvedStatement only, no proof