Definition on_path b o p :=
In b (concat (lookup_path_oram o p)).

Lemma locate_comp_block_selection :
forall o p p' lvl lvl' dlt,
(lvl < lvl')%nat ->
locate_node_in_tr (up_oram_tr o lvl dlt p') lvl' p =
locate_node_in_tr o lvl' p.