proposition: Fact andbE x y : x && y = if (x < y)%N then x else y.
proof: Proof. by case: x y => [] []. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat choice seq) mathcomp(path fintype tuple bigop finset div prime finfun) mathcomp(finset)