proposition: Lemma rVnpolyK : cancel rVnpoly npoly_rV.
proof: Proof. by move=> p /=; rewrite val_insubd [_ \is a _]size_poly rVpolyK. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq choice fintype tuple) mathcomp(bigop binomial finset finfun ssralg countalg finalg poly polydiv) mathcomp(perm fingroup matrix mxalgebra mxpoly vector countalg)