fact: Fixpoint PSubstL1 (P1: Pol) (LM1: list (Mon * Pol)) (n: nat) : Pol := match LM1 with cons (M1,P2) LM2 => PSubstL1 (PNSubst1 P1 M1 P2 n) LM2 n | _ => P1 end.
imports: Setoid Morphisms Env BinPos BinNat BinInt Ring_theory