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Planar triangulations with real chromatic roots arbitrarily close to four

Gordon F. Royle
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Abstract

We exhibit infinite families of planar graphs with real chromatic roots arbitrarily close to 4, thus resolving a long-standing conjecture in the affirmative.

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Gordon F. Royle. 2005-11-17. Planar triangulations with real chromatic roots arbitrarily close to four. https://arxiv.org/abs/math/0511304

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