Opaque Succ_e.
Fixpoint Nat_e (n:nat) : Cobham :=
match n with
| 0 => Zero
| S n' => Comp 0 Succ_e [Nat_e n']
end.

(* Specifications: *)
Lemma arity_Nat n : arity (Nat_e n) = ok_arity 0.
Lemma rec_bounded_Nat n :
rec_bounded (Nat_e n).
Lemma Nat_correct : forall n l,
length (Sem (Nat_e n) l) = n.