proposition: Lemma FA_mm' m: FA m m = ((m <=1):nat).
proof: Proof. by case: m => //m; rewrite FA_mm;case m. Qed.
imports: mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat) mathcomp(seq path fintype div bigop binomial) mathcomp(prime finset ssralg ssrnum ssrint)