“…There is not a single complexity result, and it is even unknown whether the porous exponential domination number of a given subcubic tree can be determined efficiently. Partly motivated by such difficulties, Goddard et al define [7] disjunctive domination (see also [10,11,13]), which keeps the exponential decay of the influence but only considers distances one and two. Further related parameters known as influence and total influence [6] also have unknown complexity even for trees [9].…”