proposition: Lemma lteif_andb x y : {morph lteif x y : p q / p && q}.
proof: Proof. by case=> [][] /=; case: comparableP. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat choice seq) mathcomp(path fintype tuple bigop finset div prime finfun) mathcomp(finset)