Proof using one_node_params.
intros.
rewrite removeAfterIndex_same_sufficient with (l := l'); auto.
- apply thing2; auto.
- unfold entries_match in *. intros. eapply H2; eauto.
- unfold entries_match in *. intros. eapply H2; eauto.
Qed.

Lemma sorted_findGtIndex_0 :
forall l,
(forall e, In e l -> eIndex e > 0) ->
sorted l ->
findGtIndex l 0 = l.