induction n.
simpl in |- *.
red in |- *.
auto with algebra.
intros.
apply
Trans
with
(Seqtl (op (couple (head v) (head w));; pointwise op (Seqtl v) (Seqtl w)));
auto with algebra.
Qed.
Hint Resolve pointwise_Seqtl: algebra.

Lemma pointwise_concat :
forall (A B C : Setoid) (n m : Nat) (v : seq n A)
(w : seq m A) (x : seq n B) (y : seq m B) (op : MAP (cart A B) C),
pointwise op (v ++ w) (x ++ y) =' pointwise op v x ++ pointwise op w y
in seq _ _.