(* Constructions with gr_pushs **********************************************)
(*** tls_pushs *)
-lemma gr_tls_pushs (n) (f): f = ⫱*[n] ⫯*[n] f.
+lemma gr_tls_pushs (n) (f): f = â«°*[n] ⫯*[n] f.
#n @(nat_ind_succ … n) -n //
#n #IH #f <gr_tls_swap <gr_pushs_succ <gr_tl_push //
qed.