intros.
elim
(EXPH4 (seq (ia Frame s3 lce) (K i)) (seq (Tn_d d e0) (seq (Sn e1) (S i)))
(L i) (R i)).
elim Lmers3.
elim LmerTnd.
elim LmerL.
pattern (R i) at 2 3 5 8 in |- *.
elim ProcR.
elim LmerRn.
elim CommLRn.
elim CommTn_dL.
elim CommTn_dRn.
elim Comms3Tn_d.
elim Comms3L.
elim Comms3Rn_lce.
repeat elim A6'.
repeat elim A6.
elim SC7.
pattern (R i) at 1 in |- *.
elim ProcR.
elim A5.
apply refl_equal.
Qed.

Theorem Lem6 :
forall d : D,
seq (ia Frame c3 (Tuple e0 d))
(enc H
(mer (K i)
(mer
(seq (ia D s4 d)
(seq (ia frame s5 (tuple e0)) (seq (Rn e0) (R i))))
(mer (seq (Tn_d d e0) (seq (Sn e1) (S i))) (L i))))) =
enc H
(mer (seq (ia Frame s3 (Tuple e0 d)) (K i))
(mer (seq (Tn_d d e0) (seq (Sn e1) (S i))) (mer (L i) (R i)))).