Opaque OneMinusMultPlus'_e.
Definition OneMinusMultPlus_e : Cobham :=
Comp 2 OneMinusMultPlus'_e [Comp 2 Normalize_e [Proj 2 0]; Proj 2 1].

Lemma OneMinusMultPlus_correct : forall l,
bs2nat (Sem OneMinusMultPlus_e l) =
(1 - bs2nat (hd nil l)) * bs2nat (hd nil (tl l)) +
bs2nat (hd nil l) * (1 - (1 - bs2nat (hd nil l))).