New bounds for the chromatic number of graphs
β Scribed by Manouchehr Zaker
- Publisher
- John Wiley and Sons
- Year
- 2008
- Tongue
- English
- Weight
- 184 KB
- Volume
- 58
- Category
- Article
- ISSN
- 0364-9024
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β¦ Synopsis
Abstract
In this article we first give an upper bound for the chromatic number of a graph in terms of its degrees. This bound generalizes and modifies the bound given in 11. Next, we obtain an upper bound of the order of magnitude ${\cal O}({n}^{{1}-\epsilon})$ for the coloring number of a graph with small K~2,t~ (as subgraph), where n is the order of the graph. Finally, we give some bounds for chromatic number in terms of girth and book size. These bounds improve the best known bound, in terms of order and girth, for the chromatic number of a graph when its girth is an even integer. Β© 2008 Wiley Periodicals, Inc. J Graph Theory 58:110β122, 2008
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