proposition: Fact meet_leR {x y} : (meet x y) <= y.
proof: Proof. by have:= le_refl (meet x y); rewrite meetP => /andP []. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat choice seq) mathcomp(path fintype tuple bigop finset div prime finfun) mathcomp(finset)