proposition: Lemma sub_rowg_mx (L : {set rVn}) : L \subset rowg (rowg_mx L).
proof: Proof. apply/subsetP=> v Lv; rewrite inE genmxE. by rewrite (eq_row_sub (enum_rank_in Lv v)) // rowK enum_rankK_in. Qed.
imports: HB(structures) mathcomp(ssreflect ssrbool ssrfun eqtype ssrnat seq path) mathcomp(div choice fintype tuple finfun bigop prime) mathcomp(ssralg poly finset fingroup morphism perm) mathcomp(automorphism quotient gproduct action finalg) mathcomp(zmodp commutator cyclic center pgroup gseries) mathcomp(nilpotent sylow maximal abelian matrix) mathcomp(mxalgebra mxrepresentation)