Efficient Computation of the Characteristic Polynomial of a Threshold Graph
نویسنده
چکیده
Abstract. An efficient algorithm is presented to compute the characteristic polynomial of a threshold graph. Threshold graphs were introduced by Chvátal and Hammer, as well as by Henderson and Zalcstein in 1977. A threshold graph is obtained from a one vertex graph by repeatedly adding either an isolated vertex or a dominating vertex, which is a vertex adjacent to all the other vertices. Threshold graphs are special kinds of cographs, which themselves are special kinds of graphs of clique-width 2. We obtain a running time of O(n log n) for computing the characteristic polynomial, while the previously fastest algorithm ran in quadratic time.
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عنوان ژورنال:
- Theor. Comput. Sci.
دوره 657 شماره
صفحات -
تاریخ انتشار 2015