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On graphs with strongly independent color-classes

✍ Scribed by A. Gyárfás; T. Jensen; M. Stiebitz


Publisher
John Wiley and Sons
Year
2004
Tongue
English
Weight
148 KB
Volume
46
Category
Article
ISSN
0364-9024

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✦ Synopsis


Abstract

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 G~k~ with the required property for every k. The graph G~k~ exhibits remarkable similarity to Kneser graphs. The proof that G~k~ is k‐chromatic relies on Lovász's theorem about the chromatic number of graphs with highly connected neighborhood complexes. © 2004 Wiley Periodicals, Inc. J Graph Theory 46: 1–14, 2004


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