(** Def 5 of (Rose) *)

Definition Mod2_e : Cobham :=
  Rec
    Zero
    (False_e 2)
    (One_e 2)
    (One_e 1).

Lemma DivDivTwoPower_correct : forall l, Sem DivDivTwoPower_e l = skipn (length (nth 1 l nil) - length (nth 2 l nil)) (nth 0 l nil).