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arXiv · 1503.00617

Efficient Computation of the Characteristic Polynomial of a Threshold Graph

Martin Fürer
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Abstract

An efficient algorithm is presented to compute the characteristic polynomial of a threshold graph. Threshold graphs were introduced by Chv\'atal 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 $O(n \log^2 n)$ for computing the characteristic polynomial, while the previously fastest algorithm ran in quadratic time. Keywords: Efficient Algorithms, Threshold Graphs, Characteristic Polynomial.

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Martin Fürer. 2015-03-02. Efficient Computation of the Characteristic Polynomial of a Threshold Graph. https://arxiv.org/abs/1503.00617

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