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arXiv · 0905.3487

A Simple Proof of an Inequality Connecting the Alternating Number of Independent Sets and the Decycling Number

Vadim E. Levit·Eugen Mandrescu
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Abstract

If alpha=alpha(G) is the maximum size of an independent set and s_{k} equals the number of stable sets of cardinality k in graph G, then I(G;x)=s_{0}+s_{1}x+...+s_{alpha}x^{alpha} is the independence polynomial of G. In this paper we provide an elementary proof of the inequality claiming that the absolute value of I(G;-1) is not greater than 2^phi(G), for every graph G, where phi(G) is its decycling number.

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BibTeXRIS

Vadim E. Levit, Eugen Mandrescu. 2009-05-21. A Simple Proof of an Inequality Connecting the Alternating Number of Independent Sets and the Decycling Number. https://arxiv.org/abs/0905.3487

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