proposition: Lemma stable0mx : stablemx (0 : 'M_(m, n)) f.
proof: Proof. by rewrite mul0mx. 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 finalg zmodp matrix)