On graphs with strongly independent color-classes

نویسندگان

  • András Gyárfás
  • T. Jensen
  • Michael Stiebitz
چکیده

We prove that for every k there is a k -chromatic graph with a k-coloring where the neighbors of each color-class form an independent set. This answers a question raised by N. J. A. Harvey and U. S. R. Murty [4]. In fact we find the smallest graph Gk with the required property for

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عنوان ژورنال:
  • Journal of Graph Theory

دوره 46  شماره 

صفحات  -

تاریخ انتشار 2004