proposition: Fact ltZ_def m n : (Z.ltb m n) = (n != m) && (Z.leb m n).
proof: Proof. by rewrite eqE /=; lia. Qed.
imports: Coq(ZArith) HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq path) mathcomp(div choice fintype tuple finfun bigop finset prime) mathcomp(order binomial ssralg countalg ssrnum ssrint) mathcomp(zify_ssreflect)