proposition: Lemma rowg_mx_eq0 (L : {group rVn}) : (rowg_mx L == 0) = (L :==: 1%g).
proof: Proof. rewrite -trivg_rowg; apply/idP/eqP=> [|->]; last by rewrite rowg_mx1 rowg0. exact/contraTeq/subG1_contra/sub_rowg_mx. 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)