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A Zero-Free Interval for Chromatic Polynomials of Graphs

Published online by Cambridge University Press:  12 September 2008

Bill Jackson
Affiliation:
Department of Mathematical Studies, Goldsmiths' College, London SE14 6NW, England

Abstract

Let G be a graph and P(G, t) be the chromatic polynomial of G. It is known that P(G, t) has no zeros in the intervals (−∞, 0) and (0, 1). We shall show that P(G, t) has no zeros in (1, 32/27]. In addition, we shall construct graphs whose chromatic polynomials have zeros arbitrarily close to 32/27.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1993

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References

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