摘要
极值图论是组合数学的一个分支,主要研究对于给定的一类图,确定其中某些参数的极值,所讨论的Turán数属于图论中的极值问题.图H的Turán数是指不包含H作为子图的n阶图的最大边数,记作ex(n,H).确定了ex(n,P5∪P9)=max{[n,14,5],5n-14},其中■,对应的极值图为K13∪H和K5+(K2∪Kn-7),这里H∈EX(n-13,P5).
Extremal graph theory is a branch of combinatorics mathematics.It mainly studies the extremal values of some parameters for a given family of graph.The Turán number mainly discussed in this paper belongs to the extremal problem in graph theory.The Turán number of a graph H,denoted by ex(n,H),is the maximum number of edges in any graph of order n which does not contain H as a subgraph.In this paper,we determine ex(n,P5∪P9)=max{[n,14,5],5n-14},where ■,moreover, the extremal graphs are K13∪H for ■.
作者
田宏
胡玉梅
TIAN Hong;HU Yumei(College of Mathematics,Tianjin Universty,Tianjin 300350,China)
出处
《河北师范大学学报（自然科学版）》
CAS
2021年第1期15-18,共4页
Journal of Hebei Normal University：Natural Science
