proposition: Lemma pjf_3 : forall (i j : nat) Hi Hj, n < i -> j = i - S n -> partition_join_fun i Hi [=] Q j Hj.
proof: Proof. intros; unfold partition_join_fun in |- *. generalize Hj; rewrite H0; clear Hj; intros. elim le_lt_dec; intro; simpl in |- *. exfalso; apply Nat.le_ngt with i n; auto. apply prf1; auto. Qed.
imports: CoRN.ftc.RefLemma Coq(Lia)