(* Constructions with pr_uni ************************************************)
lemma pr_nat_uni (n) (l):
- @↑❨l,𝐮❨n❩❩ ≘ l+n.
+ @§❨l,𝐮❨n❩❩ ≘ l+n.
/2 width=1 by pr_nat_pred_bi/
qed.
(* Inversions with pr_uni ***************************************************)
lemma pr_nat_inv_uni (n) (l) (k):
- @↑❨l,𝐮❨n❩❩ ≘ k → k = l+n.
+ @§❨l,𝐮❨n❩❩ ≘ k → k = l+n.
/2 width=4 by pr_nat_mono/ qed-.