(* Constructions with gr_tl *************************************************)
(*** isdiv_tl *)
-lemma gr_isd_tl (f): ð\9d\9b\80â\9dªfâ\9d« â\86\92 ð\9d\9b\80â\9dªâ«±f❫.
+lemma gr_isd_tl (f): ð\9d\9b\80â\9dªfâ\9d« â\86\92 ð\9d\9b\80â\9dªâ«°f❫.
#f cases (gr_map_split_tl f) * #H
[ elim (gr_isd_inv_push … H) -H //
| /2 width=3 by gr_isd_inv_next/