Definition nZterm : list (Term A n) -> Prop.Definition canonical (a : list (Term A n)) : Prop := olist a /\ nZterm a.

Theorem ltP_pX_canonical : forall a p, canonical p -> ~ zeroP (A:=A) A0 eqA (n:=n) a -> ltP p (pX a pO) -> canonical (pX a p).