An Unavoidable Set of D-Reducible Configurations
نویسنده
چکیده
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 [18], Appel and Haken [2] and Robertson, Sanders, Seymour and Thomas [15].
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تاریخ انتشار 2009