Edge coloring of graphs with small average degrees

نویسندگان

  • Rong Luo
  • Cun-Quan Zhang
چکیده

Let G be a simple graph with average degree . d and maximum degree . It is proved, in this paper that G is not critical if . d6 6 and ¿ 8, or . d6 20 3 and ¿ 9. This result generalizes earlier results of Vizing (Metody Diskret. Analiz. 5 (1965) 9), Mel’nikov (Mat. Zametki 7 (1970) 671) and Hind and Zhao (Discrete Math. 190 (1998) 107) and Yan and Zhao (Graphs Combin. 16 (2) (2000) 245). It also improves a result by Fiorini (Math. Proc. Cambridge Philos. Soc. 77 (1975) 475) on the number of edges of critical graphs for certain . c © 2003 Elsevier B.V. All rights reserved.

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عنوان ژورنال:
  • Discrete Mathematics

دوره 275  شماره 

صفحات  -

تاریخ انتشار 2004