proposition: Lemma neq_lt x y : (x != y) = (x < y) || (y < x).
proof: Proof. by case: ltgtP. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat choice seq) mathcomp(path fintype tuple bigop finset div prime finfun) mathcomp(finset)