proposition: Fact subZ_ge0 m n : Z.leb 0 (n - m)%R = Z.leb m n.
proof: Proof. by rewrite /GRing.add /GRing.opp /=; 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)