摘要
设G为简单图,E(G)为其边集,则G的指数型反遗忘指数e1/F(G)=∑uv∈E(G)e(1/d2G(u)+1/d2Gt(v)),其中dG(u)为G中顶点u的度.本文首先给出树的指数型反遗忘指数e1/F的极小值和对应的极图,然后研究当e1/F达到极大值时对应的极图的一些结构性质.
For a simple graph G with edge set E(G),the exponential inverse forgotten index of G is defined as e1/F(G)=∑uv∈E(G)e(1/d2G(u)+1/d2Gt(v)),where dG(u)is the degree of the vertex u in G.In this paper,firstly,we give the minimum value of exponential inverse forgotten index of a tree and determine its corresponding extremal graph.Then,we investigate the maximum value of the exponential inverse forgotten index and describe the structural characteristics of the extremal graph.
作者
曾明瑶
邓汉元
Zeng Mingyao;Deng Hanyuan(School of Mathematics and Computation Science,Huaihua University,Huaihua 418000,China;School of Mathematics and Statistics,Hunan Normal University,Changsha 410081,China)
出处
《数学理论与应用》
2022年第3期61-70,共10页
Mathematical Theory and Applications
基金
国家自然科学基金项目(No.11971164)
湖南省自然科学基金项目(No.2020JJ4423)资助。
关键词
树
指数型反遗忘指数
极值
极图
Tree
Exponential inverse forgotten index
Extremal value
Extremal graph
