proposition: Theorem dExpPrim: (dExp b < dExp b')%Z.
proof: Proof. unfold b'; simpl. cut (forall (x:N) (y:positive), (x+(Zpos y)=(x +Npos y)%N)%Z). intros T; simpl; rewrite <- T. apply Z.le_lt_trans with (N.double (dExp b)); [| lia]. rewrite N.double_spec. lia. intros;unfold Nplus. case x0; auto with zarith. Qed.
imports: Reals ZArith List PeanoNat Psatz