摘要
放宽了文献[1]中一个定理的条件,指出“3点度和”条件可减弱为对n阶图中满足min{d(x,y),d(y,z),d(z,x)}=2的任意3个独立,点x,y,z,有d(x)+d(y)+d(z)≥n。在这个条件下,相应的结果仍成立。
he condition for Theorem 2 presented in Ref.[1] is relaxed in this paper wherein itis also indicated that the condition“3-degree sum”can be reduced to any three independent ver-tices x,y and z that meet min{d(x,y),d(y,z),d(z,x)}=2 in a n-order graph,leading tod(x)+d(y) +d(z)≥n. Corresponding results will hold under this condition.
出处
《南京气象学院学报》
CSCD
1995年第4期506-510,共5页
Journal of Nanjing Institute of Meteorology
基金
国家自然科学基金
关键词
紧图
控制圈
独立点
HAMILTON图
tough graph,dominating cycle, independent vertices,Hamilton graph