(** Def 5 of (Rose) *)

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

Lemma DivTwoPower_correct_bs : forall l, Sem DivTwoPower_e l = fun_power (length (hd nil (tl l))) (@tl _) (hd nil l).