(* Anomaly see Issue #15413 Combined Scheme Even_Odd_mutsind from Even_Odd_sind, Odd_Even_sind. *)
(** additional versions of parity predicates in [Type] useful for eliminating into [Type], but still with opaque proofs *)
Definition EvenT n := { m | n = 2 * m }.
Definition OddT n := { m | n = 2 * m + 1 }.

Lemma OddT_S_EvenT n : OddT (S n) -> EvenT n.