On P4-transversals of chordal graphs
نویسنده
چکیده
A P4-transversal of a graph G is a set of vertices T which meets every P4 of G. A P4transversal T is called stable if there are no edges in the subgraph of G induced by T . It has been previously shown by Hoàng and Le that it is NP -complete to decide whether a comparability (and hence perfect) graph G has a stable P4-transversal. In the following we show that the problem is NP -complete for chordal graphs. We apply this result to show that two related problems of deciding whether a chordal graph has a P3-free P4-transversal, and deciding whether a chordal graph has a P4-free P4-transversal (also known as a two-sided P4-transversal) are both NP complete. Additionally, we strengthen the main results to strongly chordal graphs.
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 308 شماره
صفحات -
تاریخ انتشار 2008