(* Note: this might use fsb_inv_cast (still to be proved) *)
(* Basic_1: uses: ty3_sn3 *)
(* Basic_2A1: uses: nta_fwd_csn *)
-theorem nta_fwd_fsb (a) (h) (G) (L):
- â\88\80T,U. â¦\83G,Lâ¦\84 â\8a¢ T :[a,h] U →
- ∧∧ ≥[h] 𝐒⦃G,L,T⦄ & ≥[h] 𝐒⦃G,L,U⦄.
-#a #h #G #L #T #U #H
+theorem nta_fwd_fsb (h) (a) (G) (L):
+ â\88\80T,U. â\9d¨G,Lâ\9d© â\8a¢ T :[h,a] U →
+ ∧∧ ≥𝐒 ❨G,L,T❩ & ≥𝐒 ❨G,L,U❩.
+#h #a #G #L #T #U #H
elim (cnv_inv_cast … H) #X #HU #HT #_ #_ -X
-/3 width=2 by cnv_fwd_fsb, conj/
-qed-.
+/3 width=3 by cnv_fwd_fsb, conj/
+qed-.