Definition eqPf :
  forall pq, {eqP (fst pq) (snd pq)} + {~ eqP (fst pq) (snd pq)}.Definition seqP : poly A0 eqA ltM -> poly A0 eqA ltM -> Prop.

Theorem seqp_dec : forall p q : poly A0 eqA ltM, {seqP p q} + {~ seqP p q}.