Definition leader_sublog (net : network) :=
    forall leader e h,
      type (snd (nwState net leader)) = Leader ->
      In e (log (snd (nwState net h))) ->
      eTerm e = currentTerm (snd (nwState net leader)) ->
      In e (log (snd (nwState net leader))).

Lemma invalid_index : forall net h e, refined_raft_intermediate_reachable net -> In e (log (snd (nwState net h))) -> eIndex e = S (maxIndex (log (snd (nwState net h)))) -> False.