Graph Operations and Neighborhood Polynomials

Maryam Alipour; Peter Tittmann

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arXiv · 1807.03971

Graph Operations and Neighborhood Polynomials

Maryam Alipour·Peter Tittmann

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Abstract

The neighborhood polynomial of graph $G$ is the generating function for the number of vertex subsets of $G$ of which the vertices have a common neighbor in $G$. In this paper, we investigate the behavior of this polynomial under several graph operations. Specifically, we provide an explicit formula for the neighborhood polynomial of the graph obtained from a given graph $G$ by vertex attachment. We use this result to propose a recursive algorithm for the calculation of the neighborhood polynomial. Finally, we prove that the neighborhood polynomial can be found in polynomial-time in the class of $k$-degenerate graphs.

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Maryam Alipour, Peter Tittmann. 2018-07-11. Graph Operations and Neighborhood Polynomials. https://arxiv.org/abs/1807.03971

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