Grötzsch's Theorem
نویسنده
چکیده
Grötzsch’s Theorem is one of the most famous theorems in graph colouring theory. Its original proof, given in German, in 1958, was fairly complex. In 1989, Steinberg and Younger [17] gave the first correct proof, in English, of the dual version of this theorem. This essay studies the Steinberg-Younger proof in detail, putting special emphasis on improved presentation of their arguments and clarity of exposition. It also gives a new, much simpler proof that is inspired by Carsten Thomassen’s [19], but is due to an unpublished work of C. Nunes da Silva, R.B. Richter and D. Younger.
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تاریخ انتشار 2012