Closed neighborhood order dominating functions
نویسندگان
چکیده
The linear programmimg formulations of graph domination and graph packing are duals. Likewise, fractional efficient domination for a graph G has as its dual the parameter discussed in this paper, namely the minimum weight of a real-valued function f : V(G) -+ [0, (0) such that the sum of the weights in each closed neighborhood is at least its cardinality. The fractional and integer "closed neighborhood order domination" parameters, WI and W, are introduced. Deciding ifW(G) ~ k is an NPcomplete problem even for just the class of bipartite graphs or chordal graphs. A linear time algorithm for computing W (T) for an arbitrary tree T is presented. Other theoretical and computational results are presented.
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ورودعنوان ژورنال:
- Australasian J. Combinatorics
دوره 17 شماره
صفحات -
تاریخ انتشار 1998