proposition: Lemma scalemx1 n a : a *: 1%:M = a%:M :> 'M_n.
proof: Proof. by rewrite scale_scalar_mx mulr1. 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)