PDF全文下载:2011020208
张埂, 吴树猛, 焦娇
(中国矿业大学 理学院,江苏 徐州 221008)
摘要: 如果图G的正常边染色不包含2-色圈,则称它是图G的无圈边染色。图G的无圈边色数表示图G的无圈边染色所需的最小颜色数.2001年,Alon等猜想任意简单图G的无圈边色数都不超过Δ(G)+2,其中Δ(G)为图G的最大顶点度。已经证明了当Δ≤3时,此猜想成立。本研究利用线性-时间算法思想研究了最大顶点度为4的图,并给出了最大顶点度为4的图G满足此猜想的一个充分条件为图G的任意2个最大度顶点都不邻接。
关键词:图; 无圈边染色; 无圈边色数
中图分类号: O 157.5 文献标志码: A
Acyclic Edge Coloring of Graphs with Maximum Degree 4
ZHANG Geng, WU Shu-meng, JIAO Jiao
(College of Science,China University of Mining and Technology,Xuzhou 221008,China)
Abstract: If a proper edge coloring of G contains no bichromatic cycles in G,then it is an acyclic edge coloring of G. The acyclic chromatic number of G is the minimum number of colors among all the acyclic edge colorings of G. In 2001,Alon et al. conjectured that the acyclic chromatic number of any simple graph G is no more than Δ(G)+2,where Δ(G) is the maximum degree of G. This conjecture has been verified to be true when Δ≤3. In this paper,by using linear-time algorithm,we study the graphs with maximum degree 4 and prove the conjecture also hold when no two vertices of degree 4 in G are adjacent.
Key words: graphs; acyclic edge coloring; acyclic chromatic number
收稿日期:2010-07-22
作者简介: 张埂(1986—),男,硕士研究生.