摘要
设图G=G(V,E)是简单图.图扩展离心连通指数Aζc(G)是基于邻接和的指数,即Aζc(G)=∑u∈V(G)(ΠV∈N(u)dv)/e(u)其中e(u)为图顶点u的离心率,N(u)为顶点u的邻点集.本文刻画了树中具有最大、第二大、最小、第二小扩展离心连通指数的树的特征和单圈图中具有最大扩展离心连通指数的单圈图的特征.
Let G =(V,E) be a simple graph and the augmented eccentric connectivity index is an adjacency-sum-distance based index by denote Aζc(G),is defined as Aζc(G)=∑u∈V(G)(ΠV∈N(u)dv)/e(u) where e(u) is its eccentricity of vertex u.In this paper,the trees with first,second minimum and maximum Aζc(G) are characterized and the unicyclic graphs with maximum Aζc(G) are characterized.
出处
《湖南文理学院学报(自然科学版)》
CAS
2012年第1期24-27,35,共5页
Journal of Hunan University of Arts and Science(Science and Technology)
基金
湖南省教育厅科研项目(08C579)
关键词
扩展离心连通指数(Aζc(G))
树
单圈图
极值图
The augmented eccentric connectivity index(Aζc(G))
Trees
Unicyclic graphs
Extremal graphs