Cycle lengths and chromatic number of graphs
نویسندگان
چکیده
For a simple 5nite graph G let Co(G) and Ce(G) denote the set of odd cycle lengths and even cycle lengths in a graph G, respectively. We will show that the chromatic number (G) of G satis5es: (G)6min{2r + 2; 2s+ 3}6 r + s+ 2, if |Co(G)|= r and |Ce(G)|= s. c © 2004 Elsevier B.V. All rights reserved. MSC: 05C15
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ورودعنوان ژورنال:
- Discrete Mathematics
دوره 286 شماره
صفحات -
تاریخ انتشار 2004