#L elim L -L
/4 width=3 by frees_eq_repl_back, frees_gref, frees_atom, eq_push_inv_isid/
qed.
+
+(* Basic_2A1: removed theorems 27:
+ frees_eq frees_be frees_inv
+ frees_inv_sort frees_inv_gref frees_inv_lref frees_inv_lref_free
+ frees_inv_lref_skip frees_inv_lref_ge frees_inv_lref_lt
+ frees_inv_bind frees_inv_flat frees_inv_bind_O
+ frees_lref_eq frees_lref_be frees_weak
+ frees_bind_sn frees_bind_dx frees_flat_sn frees_flat_dx
+ lreq_frees_trans frees_lreq_conf
+ llor_atom llor_skip llor_total
+ llor_tail_frees llor_tail_cofrees
+*)