proposition: Lemma mulmx_is_scalable A : scalable (@mulmx _ m n p A).
proof: Proof. by move=> a B; rewrite scalemxAr. Qed.
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq choice) mathcomp(fintype finfun bigop finset fingroup perm order) mathcomp(div prime binomial ssralg countalg finalg zmodp)