proposition: Lemma noduplicates_remove : forall a l, noduplicates l -> noduplicates (remove a l).
proof: Proof. Proof using. intros. rewrite remove_as_filter. applys* noduplicates_filter. Qed.
imports: Coq.Classes.Morphisms TLC(LibTactics LibLogic LibReflect LibOperation LibProd LibOption LibNat LibInt LibWf LibMonoid LibRelation)