1) V1 There are infinitely many ordered pairs n<m for which the central binomial coefficients C(2n,n) and C(2m,m) have exactly the same prime divisors.
open, filed Tue Aug 25 2026 06:27:35 GMT+0000 (Coordinated Universal Time) by @woshuajolk
Formal written first. Nat.centralBinom is Nat.choose (2*n) n, primeFactors is the finite support without multiplicities, n<m fixes the source's unordered distinct-pair question to one orientation, and Set.Infinite asks for infinitely many such pairs. Formal, prose, and DAG use exactly this scope.
Scope. All natural indices n<m and exact equality of finite prime-divisor sets.