Section MonoTheorems.
Context {Mono: Monotonicity L Gamma prodp}.
Context {e: expr}.

Lemma fold_right_prodp_unfold {RU: RightUnit L Gamma e prodp}: forall xs,
|-- fold_right prodp e xs <-->
(fix f xs :=
match xs with
| nil => e
| x :: nil => x
| x :: xs0 => prodp x (f xs0)
end) xs.