Edge-face chromatic number and edge chromatic number of simple plane graphs

نویسندگان

  • Rong Luo
  • Cun-Quan Zhang
چکیده

Given a simple plane graph G, an edge-face k-coloring of G is a function : E(G) [ F (G) ! f1, . . . ,kg such that, for any two adjacent or incident elements a, b 2 E(G) [ F (G), (a) 61⁄4 (b). Let e(G), ef(G), and (G) denote the edge chromatic number, the edge-face chromatic number, and the maximum degree of G, respectively. In this paper, we prove that ef(G) 1⁄4 e(G) 1⁄4 (G) for any 2-connected simple plane graph G with (G) 24. 2005 Wiley Periodicals, Inc. J Graph Theory 49: 234–256, 2005

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عنوان ژورنال:
  • Journal of Graph Theory

دوره 49  شماره 

صفحات  -

تاریخ انتشار 2005