proposition: Lemma det_scalar n a : \det (a%:M : 'M[R]_n) = a ^+ n.
proof: Proof. by rewrite -{1}(mulr1 a) -scale_scalar_mx detZ det1 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)