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arXiv · 0905.0043

An unavoidable set of D-reducible configurations

John Steinberger
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Abstract

We give a new proof of the four-color theorem by exhibiting an unavoidable set of 2822 D-reducible configurations. The existence of such a set had been conjectured by several researchers including Stromquist, Appel and Haken, and Robertson, Sanders, Seymour and Thomas.

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John Steinberger. 2009-05-04. An unavoidable set of D-reducible configurations. https://arxiv.org/abs/0905.0043

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