摘要
让W_(n,n-2)表示删去轮形图W_n中一条轮辐所得到的图.W(n,n-2,k)表示在W_(n,n-2)中由k个点u_1,u_2,…,u_t组成的独立集取代W_(n,n-2)中的2度点u,使得u_j(j=1,2,…,k)仅与u所相邻的两个点x,y相邻接而得到的。本文证明了当k=2,n≥4为偶数时,这类图是色唯一的。
Let Wn,n-2 denote the graph of order n obtained from a wheel Wn by deleting a wheel spoke. Let u be the vertex of degree 2 in Wn,n-2,and let x,y be the two vertices adjacent to u . For k>1, letW(n,n-2,k) be the graph ob-tained from Wn,n-2 by replacing u with an independent set of k vertices u1,...,uk, such that uj is adjacent only to x and y for each j=1,...,k . It is proved that graphs like W(n,n-2,k) are chromatically unique if k =2,n>4 is even.
出处
《北京理工大学学报》
EI
CAS
CSCD
1993年第2期208-212,共5页
Transactions of Beijing Institute of Technology
基金
国家自然科学基金
关键词
无向图
轮形图
色多项式
色唯一性
undirected graphs/wheel graphs
chromatic polynomials
chromatic equivalent
chromatically unique
