fact: Fixpoint PSubstL (P1: Pol) (LM1: list ((C * Mon) * Pol)) (n: nat) : option Pol := match LM1 with cons (M1,P2) LM2 => match PNSubst P1 M1 P2 n with Some P3 => Some (PSubstL1 P3 LM2 n) | None => PSubstL P1 LM2 n end | _ => None end.
imports: Setoid Morphisms BinList BinPos BinNat BinInt Ring_theory