proposition: Lemma det1 n : \det (1%:M : 'M[R]_n) = 1.
proof: Proof. by rewrite -perm_mx1 det_perm odd_perm1. 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)