intros l; pattern l in |- *.
apply (well_founded_ind (wf_lessP3 A n)).
intros x; case x; intros p z; case z; intros q r; simpl in |- *; clear x z;
auto.
case p.
rewrite <- pO_pluspf_inv1; auto.
case q.
intros a l0; rewrite <- pO_pluspf_inv1; rewrite <- pO_pluspf_inv2; auto.
case r; simpl in |- *; auto.
intros a l0 a0 l1; rewrite <- pO_pluspf_inv2; rewrite <- pO_pluspf_inv2; auto.
intros a l0 a0 l1 a1 l2 H' H'0 H'1 H'2.
cut (canonical A0 eqA ltM (pX a l0)); [ clear H'2; intros H'2 | auto ].
cut (canonical A0 eqA ltM (pX a0 l1)); [ clear H'1; intros H'1 | auto ].
cut (canonical A0 eqA ltM (pX a1 l2)); [ clear H'0; intros H'0 | auto ].
cut (canonical A0 eqA ltM l0);
[ intros C0 | apply canonical_imp_canonical with (a := a) ];
auto.
cut (canonical A0 eqA ltM l1);
[ intros C1 | apply canonical_imp_canonical with (a := a0) ];
auto.
cut (canonical A0 eqA ltM l2);
[ intros C2 | apply canonical_imp_canonical with (a := a1) ];
auto.
cut (~ zeroP (A:=A) A0 eqA (n:=n) a);
[ intros nZ0 | apply (canonical_nzeroP _ A0 eqA _ ltM) with (p := l0) ];
auto.
cut (~ zeroP (A:=A) A0 eqA (n:=n) a0);
[ intros nZ1 | apply (canonical_nzeroP _ A0 eqA _ ltM) with (p := l1) ];
auto.
cut (~ zeroP (A:=A) A0 eqA (n:=n) a1);
[ intros nZ2 | apply (canonical_nzeroP _ A0 eqA _ ltM) with (p := l2) ];
auto.
change
(eqP A eqA n (pluspf (pluspf (pX a1 l2) (pX a0 l1)) (pX a l0))
(pluspf (pX a1 l2) (pluspf (pX a0 l1) (pX a l0))))
in |- *.
case (ltT_dec A n ltM ltM_dec a1 a0);
[ intros H0; case H0; clear H0 | idtac ]; intros H0.
case (ltT_dec A n ltM ltM_dec a0 a); [ intros H1; case H1; clear H1 | idtac ];
intros H1.
cut (ltT ltM a1 a);
[ intros Ord0 | apply (ltT_trans A _ _ os) with (y := a0) ];
auto.
rewrite <- (pluspf_inv2_eq a1 a0 l2 l1); auto.
rewrite <- (pluspf_inv2_eq a0 a (pluspf (pX a1 l2) l1) l0); auto.
rewrite <- (pluspf_inv2_eq a0 a l1 l0); auto.
rewrite <- (pluspf_inv2_eq a1 a l2 (pluspf (pX a0 l1) l0)); auto.
apply eqpP1; auto.
rewrite (pluspf_inv2_eq a1 a0 l2 l1); auto.
apply H' with (y := (pX a1 l2, (pX a0 l1, l0))); simpl in |- *; auto.
red in |- *; red in |- *; simpl in |- *; auto with arith.
repeat rewrite (fun a b : nat => plus_comm a (S b)); simpl in |- *.
repeat rewrite (plus_comm (size A n l1)); auto.
rewrite <- (pluspf_inv1_eq a0 a l1 l0); auto.
rewrite <- (pluspf_inv2_eq a1 a0 l2 l1); auto.
rewrite <- (pluspf_inv2_eq a1 a0 l2 (pluspf l1 (pX a l0))); auto.
rewrite <- (pluspf_inv1_eq a0 a (pluspf (pX a1 l2) l1) l0); auto.
apply eqpP1; auto.
apply H' with (y := (pX a1 l2, (l1, pX a l0))); simpl in |- *; auto.
red in |- *; red in |- *; simpl in |- *; auto with arith.
cut (ltT ltM a1 a); [ intros Ord0 | apply eqT_compat_ltTr with (b := a0) ];
auto.
case (zeroP_dec A A0 eqA eqA_dec n (plusTerm (A:=A) plusA (n:=n) a0 a));
intros Z0.
rewrite <- (pluspf_inv3a_eq a0 a l1 l0); auto.
rewrite <- (pluspf_inv2_eq a1 a0 l2 l1); auto.
rewrite <- (pluspf_inv3a_eq a0 a (pluspf (pX a1 l2) l1) l0); auto.
apply H' with (y := (pX a1 l2, (l1, l0))); simpl in |- *; auto.
red in |- *; red in |- *; simpl in |- *; auto with arith.
repeat rewrite (fun a b : nat => plus_comm a (S b)); simpl in |- *.
repeat rewrite (plus_comm (size A n l2)); auto.
repeat rewrite (plus_comm (size A n l1)); auto.
cut (ltT ltM a1 (plusTerm (A:=A) plusA (n:=n) a0 a));
[ intros Ord1
| apply eqT_compat_ltTr with (b := a0); auto; apply (eqT_sym A n);
apply (plusTerm_eqT1 A plusA n) ]; auto.
rewrite <- (pluspf_inv2_eq a1 a0 l2 l1); auto.
rewrite <- (pluspf_inv3b_eq a0 a l1 l0); auto.
rewrite <- (pluspf_inv3b_eq a0 a (pluspf (pX a1 l2) l1) l0); auto.
rewrite <-
(pluspf_inv2_eq a1 (plusTerm (A:=A) plusA (n:=n) a0 a) l2 (pluspf l1 l0))
; auto.
apply eqpP1; auto.
apply H' with (y := (pX a1 l2, (l1, l0))); simpl in |- *; auto.
red in |- *; red in |- *; simpl in |- *; auto with arith.
repeat rewrite (fun a b : nat => plus_comm a (S b)); simpl in |- *.
repeat rewrite (plus_comm (size A n l2)); auto.
repeat rewrite (plus_comm (size A n l1)); auto.
rewrite <- (pluspf_inv1_eq a1 a0 l2 l1); auto.
case (ltT_dec A n ltM ltM_dec a0 a); [ intros H1; case H1; clear H1 | idtac ];
intros H1.
rewrite <- (pluspf_inv2_eq a0 a l1 l0); auto.
case (ltT_dec A n ltM ltM_dec a1 a); [ intros H2; case H2; clear H2 | idtac ];
intros H2.
rewrite <- (pluspf_inv2_eq a1 a (pluspf l2 (pX a0 l1)) l0); auto.
rewrite <- (pluspf_inv2_eq a1 a l2 (pluspf (pX a0 l1) l0)); auto.
apply eqpP1; auto.
rewrite (pluspf_inv1_eq a1 a0 l2 l1); auto.
apply H' with (y := (pX a1 l2, (pX a0 l1, l0))); simpl in |- *; auto.
red in |- *; red in |- *; simpl in |- *; auto with arith.
repeat rewrite (fun a b : nat => plus_comm a (S b)); simpl in |- *.
repeat rewrite (plus_comm (size A n l1)); auto.
rewrite <- (pluspf_inv1_eq a1 a l2 (pluspf (pX a0 l1) l0)); auto.
rewrite <- (pluspf_inv1_eq a1 a (pluspf l2 (pX a0 l1)) l0); auto.
apply eqpP1; auto.
rewrite (pluspf_inv2_eq a0 a l1 l0); auto.
apply H' with (y := (l2, (pX a0 l1, pX a l0))); simpl in |- *; auto.
red in |- *; red in |- *; simpl in |- *; auto.
cut (ltT ltM a0 (plusTerm (A:=A) plusA (n:=n) a1 a));
[ intros Ord1
| apply eqT_compat_ltTr with (b := a1); auto; apply (eqT_sym A n);
apply (plusTerm_eqT1 A plusA n) ]; auto.
case (zeroP_dec A A0 eqA eqA_dec n (plusTerm (A:=A) plusA (n:=n) a1 a));
intros Z0.
rewrite <- (pluspf_inv3a_eq a1 a (pluspf l2 (pX a0 l1)) l0); auto.
rewrite <- (pluspf_inv3a_eq a1 a l2 (pluspf (pX a0 l1) l0)); auto.
apply H' with (y := (l2, (pX a0 l1, l0))); simpl in |- *; auto.
red in |- *; red in |- *; simpl in |- *; auto with arith.
rewrite <- (pluspf_inv3b_eq a1 a (pluspf l2 (pX a0 l1)) l0); auto.
rewrite <- (pluspf_inv3b_eq a1 a l2 (pluspf (pX a0 l1) l0)); auto.
apply eqpP1; auto.
apply H' with (y := (l2, (pX a0 l1, l0))); simpl in |- *; auto.
red in |- *; red in |- *; simpl in |- *; auto with arith.
cut (ltT ltM a a1);
[ intros Ord0 | apply (ltT_trans A n ltM os) with (y := a0) ];
auto with arith.
rewrite <- (pluspf_inv1_eq a0 a l1 l0); auto.
rewrite <- (pluspf_inv1_eq a1 a0 l2 (pluspf l1 (pX a l0))); auto.
rewrite <- (pluspf_inv1_eq a1 a (pluspf l2 (pX a0 l1)) l0); auto.
apply eqpP1; auto.
rewrite (pluspf_inv1_eq a0 a l1 l0); auto.
apply H' with (y := (l2, (pX a0 l1, pX a l0))); simpl in |- *; auto.
red in |- *; red in |- *; simpl in |- *; auto.
cut (ltT ltM a a1);
[ intros Ord0 | apply eqT_compat_ltTl with (b := a0); auto ];
auto.
case (zeroP_dec A A0 eqA eqA_dec n (plusTerm (A:=A) plusA (n:=n) a0 a));
intros Z0.
rewrite <- (pluspf_inv3a_eq a0 a l1 l0); auto.
rewrite <- (pluspf_inv1_eqa a1 l2 (pluspf l1 l0)); auto.
rewrite <- (pluspf_inv1_eq a1 a (pluspf l2 (pX a0 l1)) l0); auto.
apply eqpP1; auto.
apply
(eqp_trans _ _ _ _ _ _ _ _ _ cs n)
with (y := pluspf l2 (pluspf (pX a0 l1) (pX a l0)));
auto.
apply H' with (y := (l2, (pX a0 l1, pX a l0))); simpl in |- *; auto.
red in |- *; red in |- *; simpl in |- *; auto.
rewrite <- (pluspf_inv3a_eq a0 a l1 l0); auto.
apply order_pluspf; auto.
apply canonical_skip_fst with (b := a0); auto.
apply canonical_skip_fst with (b := a); auto.
cut (ltT ltM (plusTerm (A:=A) plusA (n:=n) a0 a) a1);
[ intros Ord1
| apply eqT_compat_ltTl with (b := a0); auto; apply (eqT_sym A n); auto;
apply (plusTerm_eqT1 A plusA n) ]; auto.
rewrite <- (pluspf_inv3b_eq a0 a l1 l0); auto.
rewrite <- (pluspf_inv1_eq a1 a (pluspf l2 (pX a0 l1)) l0); auto.
rewrite <-
(pluspf_inv1_eq a1 (plusTerm (A:=A) plusA (n:=n) a0 a) l2 (pluspf l1 l0))
; auto.
apply eqpP1; auto.
apply
(eqp_trans _ _ _ _ _ _ _ _ _ cs n)
with (y := pluspf l2 (pluspf (pX a0 l1) (pX a l0)));
auto.
apply H' with (y := (l2, (pX a0 l1, pX a l0))); simpl in |- *; auto.
red in |- *; red in |- *; simpl in |- *; auto.
rewrite <- (pluspf_inv3b_eq a0 a l1 l0); auto.
case (zeroP_dec A A0 eqA eqA_dec n (plusTerm (A:=A) plusA (n:=n) a1 a0));
intros Z0.
rewrite <- (pluspf_inv3a_eq a1 a0 l2 l1); auto.
case (ltT_dec A n ltM ltM_dec a1 a); [ intros H2; case H2; clear H2 | idtac ];
intros H2.
cut (ltT ltM a0 a); [ intros Ord0 | apply eqT_compat_ltTl with (b := a1) ];
auto.
rewrite <- (pluspf_inv2_eq a0 a l1 l0); auto.
rewrite <- (pluspf_inv2_eq a1 a l2 (pluspf (pX a0 l1) l0)); auto.
apply
(eqp_trans _ _ _ _ _ _ _ _ _ cs n)
with (y := pX a (pluspf (pluspf (pX a1 l2) (pX a0 l1)) l0));
auto.
rewrite <- (pluspf_inv3a_eq a1 a0 l2 l1); auto.
rewrite <- (pluspf_inv2_eqa a (pluspf l2 l1) l0); auto.
apply order_pluspf; auto.
apply canonical_skip_fst with (b := a1); auto.
apply canonical_skip_fst with (b := a0); auto.
apply eqpP1; auto.
apply H' with (y := (pX a1 l2, (pX a0 l1, l0))); simpl in |- *; auto.
red in |- *; red in |- *; simpl in |- *; auto with arith.
repeat rewrite (fun a b : nat => plus_comm a (S b)); simpl in |- *.
repeat rewrite (plus_comm (size A n l1)); auto.
cut (ltT ltM a a0); [ intros Ord0 | apply eqT_compat_ltTr with (b := a1) ];
auto.
rewrite <- (pluspf_inv1_eq a0 a l1 l0); auto.
rewrite <- (pluspf_inv3a_eq a1 a0 l2 (pluspf l1 (pX a l0))); auto.
apply H' with (y := (l2, (l1, pX a l0))); simpl in |- *; auto.
red in |- *; red in |- *; simpl in |- *; auto with arith.
case (zeroP_dec A A0 eqA eqA_dec n (plusTerm (A:=A) plusA (n:=n) a0 a));
intros Z1.
cut (eqT a0 a);
[ intros eqTerm0
| apply (eqT_trans A n) with (y := a1); auto; apply (eqT_sym A n) ];
auto.
cut (eqT a (plusTerm (A:=A) plusA (n:=n) a1 a0));
[ intros eqTerm1
| apply (eqT_trans A n) with (y := a0); auto; apply (eqT_sym A n); auto;
apply (plusTerm_eqT2 A plusA n) ]; auto.
cut (eqT (plusTerm (A:=A) plusA (n:=n) a a1) a0);
[ intros eqTerm2
| apply (eqT_trans A n) with (y := a);
[ apply (plusTerm_eqT1 A plusA n)
| apply (eqT_trans A n) with (y := a1) ]; auto;
apply (eqT_sym A n) ]; auto.
cut (eqT (plusTerm (A:=A) plusA (n:=n) a1 a) a0);
[ intros eqTerm3
| apply (eqT_trans A n) with (y := a); auto;
[ apply (plusTerm_eqT2 A plusA n) | apply (eqT_sym A n) ] ];
auto.
cut (eqT a1 (plusTerm (A:=A) plusA (n:=n) a a0));
[ intros eqTerm4
| apply (eqT_trans A n) with (y := a0); auto; apply (eqT_sym A n);
apply (plusTerm_eqT2 A plusA n); auto; apply (eqT_sym A n) ];
auto.
cut (eqT a1 (plusTerm (A:=A) plusA (n:=n) a0 a));
[ intros eqTerm5
| apply (eqT_trans A n) with (y := a0); auto; apply (eqT_sym A n);
apply (plusTerm_eqT1 A plusA n) ]; auto.
rewrite <- (pluspf_inv3a_eq a0 a l1 l0); auto.
rewrite <- (pluspf_inv2_eqa a (pluspf l2 l1) l0); auto.
rewrite <- (pluspf_inv1_eqa a1 l2 (pluspf l1 l0)); auto.
apply eqpP1; auto.
apply
(eqTerm_trans _ _ _ _ _ _ _ _ _ cs n)
with
(y := plusTerm (A:=A) plusA (n:=n) a (plusTerm (A:=A) plusA (n:=n) a1 a0));
auto.
apply zeroP_plusTermr with (1 := cs); auto.
apply
(eqTerm_trans _ _ _ _ _ _ _ _ _ cs n)
with
(y := plusTerm (A:=A) plusA (n:=n) a1 (plusTerm (A:=A) plusA (n:=n) a0 a));
auto.
apply
(eqTerm_trans _ _ _ _ _ _ _ _ _ cs n)
with
(y := plusTerm (A:=A) plusA (n:=n) a1 (plusTerm (A:=A) plusA (n:=n) a a0));
auto.
apply
(eqTerm_trans _ _ _ _ _ _ _ _ _ cs n)
with
(y := plusTerm (A:=A) plusA (n:=n) (plusTerm (A:=A) plusA (n:=n) a a1) a0);
auto.
apply (eqTerm_sym _ _ _ _ _ _ _ _ _ cs n);
apply plusTerm_assoc with (1 := cs); auto.
apply (eqT_sym A n); auto.
apply (eqT_sym A n); auto.
apply
(eqTerm_trans _ _ _ _ _ _ _ _ _ cs n)
with
(y := plusTerm (A:=A) plusA (n:=n) (plusTerm (A:=A) plusA (n:=n) a1 a) a0);
auto.
apply plusTerm_comp_l with (1 := cs); auto.
apply plusTerm_com with (1 := cs); auto.
apply (eqT_sym A n); auto.
apply plusTerm_assoc with (1 := cs); auto.
apply plusTerm_comp_r with (1 := cs); auto.
apply plusTerm_com with (1 := cs); auto.
apply (eqT_sym A n); auto.
apply (eqTerm_sym _ _ _ _ _ _ _ _ _ cs n);
apply zeroP_plusTermr with (1 := cs); auto.
apply H' with (y := (l2, (l1, l0))); simpl in |- *; auto.
red in |- *; red in |- *; simpl in |- *; auto with arith.
apply order_pluspf; auto.
apply canonical_pX_eqT with (a := a0); auto.
apply (eqT_sym A n); auto.
apply canonical_pX_eqT with (a := a); auto.
apply (eqT_sym A n); auto.
apply order_pluspf; auto.
apply canonical_pX_eqT with (a := a1); auto.
apply canonical_pX_eqT with (a := a0); auto.
cut (eqT a0 a);
[ intros Ord0
| apply (eqT_trans A n) with (y := a1); auto; apply (eqT_sym A n) ];
auto.
cut (eqT a (plusTerm (A:=A) plusA (n:=n) a1 a0));
[ intros eqTerm1
| apply (eqT_trans A n) with (y := a0); auto; apply (eqT_sym A n); auto;
apply (plusTerm_eqT2 A plusA n) ]; auto.
rewrite <- (pluspf_inv3b_eq a0 a l1 l0); auto.
rewrite <-
(pluspf_inv3b_eq a1 (plusTerm (A:=A) plusA (n:=n) a0 a) l2 (pluspf l1 l0))
; auto.
rewrite <- (pluspf_inv2_eqa a (pluspf l2 l1) l0); auto.
apply eqpP1; auto.
apply
(eqTerm_trans _ _ _ _ _ _ _ _ _ cs n)
with
(y := plusTerm (A:=A) plusA (n:=n) a (plusTerm (A:=A) plusA (n:=n) a1 a0));
auto.
apply zeroP_plusTermr with (1 := cs); auto.
apply
(eqTerm_trans _ _ _ _ _ _ _ _ _ cs n)
with
(y := plusTerm (A:=A) plusA (n:=n) (plusTerm (A:=A) plusA (n:=n) a1 a0) a);
auto.
apply plusTerm_com with (1 := cs); auto.
apply plusTerm_assoc with (1 := cs); auto.
apply (eqT_sym A n); auto.
apply H' with (y := (l2, (l1, l0))); simpl in |- *; auto.
red in |- *; red in |- *; simpl in |- *; auto with arith.
apply order_pluspf; auto.
apply canonical_pX_eqT with (a := a1); auto.
apply canonical_pX_eqT with (a := a0); auto.
apply (eqT_trans A n) with (y := a); auto; apply (eqT_sym A n); auto.
apply (plusTerm_eqT2 A plusA n); auto.
red in |- *; intros H'3; absurd (zeroP (A:=A) A0 eqA (n:=n) a); auto.
apply
zeroP_comp_eqTerm
with
(1 := cs)
(a := plusTerm (A:=A) plusA (n:=n) a1 (plusTerm (A:=A) plusA (n:=n) a0 a));
auto.
apply
(eqTerm_trans _ _ _ _ _ _ _ _ _ cs n)
with
(y := plusTerm (A:=A) plusA (n:=n) (plusTerm (A:=A) plusA (n:=n) a1 a0) a);
auto.
apply (eqTerm_sym _ _ _ _ _ _ _ _ _ cs n);
apply plusTerm_assoc with (1 := cs); auto.
apply (eqT_sym A n); auto.
apply (eqTerm_sym _ _ _ _ _ _ _ _ _ cs n);
apply zeroP_plusTerml with (1 := cs); auto.
apply (eqT_sym A n); auto.
rewrite <- (pluspf_inv3b_eq a1 a0 l2 l1); auto.
case (ltT_dec A n ltM ltM_dec a0 a); [ intros H1; case H1; clear H1 | idtac ];
intros H1.
cut (ltT ltM a1 a);
[ intros Ord0
| apply eqT_compat_ltTl with (b := a0); auto; apply (eqT_sym A n) ];
auto.
cut (ltT ltM (plusTerm (A:=A) plusA (n:=n) a1 a0) a);
[ intros Ord1
| apply eqT_compat_ltTl with (b := a1); auto; apply (eqT_sym A n);
apply (plusTerm_eqT1 A plusA n) ]; auto.
rewrite <- (pluspf_inv2_eq a0 a l1 l0); auto.
rewrite <- (pluspf_inv2_eq a1 a l2 (pluspf (pX a0 l1) l0)); auto.
rewrite <-
(pluspf_inv2_eq (plusTerm (A:=A) plusA (n:=n) a1 a0) a (pluspf l2 l1) l0)
; auto.
apply eqpP1; auto.
apply
(eqp_trans _ _ _ _ _ _ _ _ _ cs n)
with (y := pluspf (pluspf (pX a1 l2) (pX a0 l1)) l0);
auto.
rewrite <- (pluspf_inv3b_eq a1 a0 l2 l1); auto.
apply H' with (y := (pX a1 l2, (pX a0 l1, l0))); simpl in |- *; auto.
red in |- *; red in |- *; simpl in |- *; auto with arith.
repeat rewrite (fun a b : nat => plus_comm a (S b)); simpl in |- *.
repeat rewrite (plus_comm (size A n l1)); auto.
cut (ltT ltM a a1);
[ intros Ord0
| apply eqT_compat_ltTr with (b := a0); auto; apply (eqT_sym A n) ];
auto.
cut (ltT ltM a (plusTerm (A:=A) plusA (n:=n) a1 a0));
[ intros Ord1
| apply eqT_compat_ltTr with (b := a0); auto; apply (eqT_sym A n);
apply (plusTerm_eqT2 A plusA n) ]; auto.
rewrite <- (pluspf_inv1_eq a0 a l1 l0); auto.
rewrite <- (pluspf_inv3b_eq a1 a0 l2 (pluspf l1 (pX a l0))); auto.
rewrite <-
(pluspf_inv1_eq (plusTerm (A:=A) plusA (n:=n) a1 a0) a (pluspf l2 l1) l0)
; auto.
apply eqpP1; auto.
apply H' with (y := (l2, (l1, pX a l0))); simpl in |- *; auto.
red in |- *; red in |- *; simpl in |- *; auto with arith.
cut (eqT a1 (plusTerm (A:=A) plusA (n:=n) a0 a));
[ intros eqTerm1
| apply (eqT_trans A n) with (y := a0); auto; apply (eqT_sym A n);
apply (plusTerm_eqT1 A plusA n) ]; auto.
cut (eqT a1 a);
[ intros eqT0
| apply (eqT_trans A n) with (y := a0); auto; apply (eqT_sym A n) ];
auto.
case (zeroP_dec A A0 eqA eqA_dec n (plusTerm (A:=A) plusA (n:=n) a0 a));
intros Z1.
rewrite <- (pluspf_inv3a_eq a0 a l1 l0); auto.
rewrite <- (pluspf_inv1_eqa a1 l2 (pluspf l1 l0)); auto.
cut
(~
zeroP (A:=A) A0 eqA (n:=n)
(plusTerm (A:=A) plusA (n:=n) (plusTerm (A:=A) plusA (n:=n) a1 a0) a));
[ intros Z2 | idtac ].
rewrite <-
(pluspf_inv3b_eq (plusTerm (A:=A) plusA (n:=n) a1 a0) a (pluspf l2 l1) l0)
; auto.
apply eqpP1; auto.
apply
(eqTerm_trans _ _ _ _ _ _ _ _ _ cs n)
with
(y := plusTerm (A:=A) plusA (n:=n) a1 (plusTerm (A:=A) plusA (n:=n) a0 a));
auto.
apply plusTerm_assoc with (1 := cs); auto.
apply (eqT_sym A n); auto.
apply (eqTerm_sym _ _ _ _ _ _ _ _ _ cs n);
apply zeroP_plusTermr with (1 := cs); auto.
apply H' with (y := (l2, (l1, l0))); simpl in |- *; auto.
red in |- *; red in |- *; simpl in |- *; auto with arith.
apply (eqT_trans A n) with (y := a1); auto.
apply (plusTerm_eqT1 A plusA n); auto.
red in |- *; intros H'3; absurd (zeroP (A:=A) A0 eqA (n:=n) a1); auto.
apply
zeroP_comp_eqTerm
with
(1 := cs)
(a := plusTerm (A:=A) plusA (n:=n) (plusTerm (A:=A) plusA (n:=n) a1 a0) a);
auto.
apply
(eqTerm_trans _ _ _ _ _ _ _ _ _ cs n)
with
(y := plusTerm (A:=A) plusA (n:=n) a1 (plusTerm (A:=A) plusA (n:=n) a0 a));
auto.
apply plusTerm_assoc with (1 := cs); auto.
apply (eqT_sym A n); auto.
apply (eqTerm_sym _ _ _ _ _ _ _ _ _ cs n);
apply zeroP_plusTermr with (1 := cs); auto.
apply order_pluspf; auto.
apply canonical_pX_eqT with (a := a0); auto.
apply (eqT_trans A n) with a; auto.
apply (eqT_sym A n); auto.
apply canonical_pX_eqT with (a := a); auto.
apply (eqT_sym A n); auto.
rewrite <- (pluspf_inv3b_eq a0 a l1 l0); auto.
cut
(eqTerm eqA
(plusTerm (A:=A) plusA (n:=n) (plusTerm (A:=A) plusA (n:=n) a1 a0) a)
(plusTerm (A:=A) plusA (n:=n) a1 (plusTerm (A:=A) plusA (n:=n) a0 a)));
[ intros eqTerm0 | idtac ].
case
(zeroP_dec A A0 eqA eqA_dec n
(plusTerm (A:=A) plusA (n:=n) (plusTerm (A:=A) plusA (n:=n) a1 a0) a));
intros Z2.
rewrite <-
(pluspf_inv3a_eq (plusTerm (A:=A) plusA (n:=n) a1 a0) a (pluspf l2 l1) l0)
; auto.
rewrite <-
(pluspf_inv3a_eq a1 (plusTerm (A:=A) plusA (n:=n) a0 a) l2 (pluspf l1 l0))
; auto.
apply H' with (y := (l2, (l1, l0))); simpl in |- *; auto.
red in |- *; red in |- *; simpl in |- *; auto with arith.
apply
zeroP_comp_eqTerm
with
(1 := cs)
(a := plusTerm (A:=A) plusA (n:=n) (plusTerm (A:=A) plusA (n:=n) a1 a0) a);
auto.
apply (eqT_trans A n) with (y := a0); auto.
apply (plusTerm_eqT2 A plusA n); auto.
rewrite <-
(pluspf_inv3b_eq (plusTerm (A:=A) plusA (n:=n) a1 a0) a (pluspf l2 l1) l0)
; auto.
rewrite <-
(pluspf_inv3b_eq a1 (plusTerm (A:=A) plusA (n:=n) a0 a) l2 (pluspf l1 l0))
; auto.
apply eqpP1; auto.
apply H' with (y := (l2, (l1, l0))); simpl in |- *; auto.
red in |- *; red in |- *; simpl in |- *; auto with arith.
apply
nzeroP_comp_eqTerm
with
(1 := cs)
(a := plusTerm (A:=A) plusA (n:=n) (plusTerm (A:=A) plusA (n:=n) a1 a0) a);
auto.
apply (eqT_trans A n) with (y := a0); auto.
apply (plusTerm_eqT2 A plusA n); auto.
apply plusTerm_assoc with (1 := cs); auto.
apply (eqT_sym A n); auto.
Qed.

Theorem pluspf_assoc :
forall p q r,
canonical A0 eqA ltM p ->
canonical A0 eqA ltM q ->
canonical A0 eqA ltM r ->
eqP A eqA n (pluspf (pluspf p q) r) (pluspf p (pluspf q r)).