proposition: Lemma subv_adjoin_seq U xs : (U <= <<U & xs>>)%VS.
proof: Proof. by rewrite (subv_trans (sub_agenv _)) // ?agenvS ?addvSl. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat seq path) mathcomp(choice fintype div tuple finfun bigop ssralg) mathcomp(finalg zmodp matrix vector poly)