Definition Dmult :
  forall (a : Term A n) (nZa : ~ zeroP (A:=A) A0 eqA (n:=n) a),
  list (Term A n) -> list (Term A n) -> list (Term A n).

Theorem divpf_comp : forall (a b : Term A n) (p q : list (Term A n)), eqP A eqA n p q -> canonical A0 eqA ltM p -> canonical A0 eqA ltM q -> eqTerm (A:=A) eqA (n:=n) a b -> forall (nZa : ~ zeroP (A:=A) A0 eqA (n:=n) a) (nZb : ~ zeroP (A:=A) A0 eqA (n:=n) b), eqP A eqA n (divpf a nZa p) (divpf b nZb q).