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import FormalConjecturesUtilErdős Problem 1094
namespace Erdos1094
open scoped Nat
For all $n\ge 2k$ the least prime factor of $\binom{n}{k}$ is $\le\max(n/k,k)$, with only finitely many exceptions.
@[category research open, AMS 11]
theorem erdos_1094 :
{(n, k) : ℕ × ℕ | 0 < k ∧ 2 * k ≤ n ∧ (n.choose k).minFac > max (n / k) k}.Finite := ⊢ {(n, k) | 0 < k ∧ 2 * k ≤ n ∧ (n.choose k).minFac > max (n / k) k}.Finite
All goals completed! 🐙
end Erdos1094