proposition: Fact anti: antisymmetric le.
proof: Proof. move=> x y /andP []; elim: x y => [|x sx ih] [|y sy] //=. by case: comparableP => //= -> lesxsy /(ih _ lesxsy) ->. Qed.
imports: HB(structures) mathcomp(ssreflect ssrfun ssrbool eqtype ssrnat choice seq) mathcomp(path fintype tuple bigop finset div prime finfun) mathcomp(finset)