proposition: Lemma vs2mxK : cancel vs2mx mx2vs.
proof: Proof. by move=> v; apply: val_inj; rewrite /= gen_vs2mx. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice) mathcomp(fintype bigop finfun tuple) mathcomp(ssralg matrix mxalgebra zmodp)