圆色数在若干图运算下的不变性  

The Invariance of Circular Chromatic Number Under Some Graph Operations

作　　者：高杨[1] 刘钢 

机构地区：[1]宿州学院数学与统计学院,安徽宿州234000

出　　处：《宿州学院学报》2011年第2期11-12,共2页Journal of Suzhou University

基　　金：宿州学院校级自然科学研究项目(2009yzk24;2009yzk18)

摘　　要：研究了圆色数在一些图运算下的不变性,并利用这些图运算:由已知圆色数为r=kd的图,构造出若干类圆色数为r的图。从一个已知圆色数为r的图(如Gkd),分别借助于图的单一顶点合并、双重顶点合并以及笛卡尔积3种运算,得到了3类圆色数为r的图。We study the invariance of circularchromatic number under some graph operations.From a given graph with circular chromatic number r=k/d,by using these operations,we construct some family of graphs whose circular chromatic number is also r.From a graph whose circular chromatic number is r,such as Gkd,by using the single-vertex identification,double-vertices identification and Cartesian product respectively,we obtain three classes of graphs in which every graph has circular chromatic number r.

关 键 词：r-染色 圆色数 色数 不变性 

分 类 号：O157.5[理学—数学]