proposition: Lemma mulKmx m : {in unitmx, @left_loop _ 'M_(n, m) invmx mulmx}.
proof: Proof. by move=> A uA /= B; rewrite mulmxA mulVmx ?mul1mx. 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)