proposition: Lemma lteif_imply C1 C2 x y : C1 ==> C2 -> x < y ?<= if C1 -> x < y ?<= if C2.
proof: Proof. by case: C1 C2 => [][] //= _ /ltW. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat choice seq) mathcomp(path fintype tuple bigop finset div prime finfun) mathcomp(finset)