proposition: Lemma row_free_map m n (A : 'M_(m, n)) : row_free A^f = row_free A.
proof: Proof. by rewrite /row_free mxrank_map. 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)