Sharp bounds for the second Zagreb index of unicyclic graphs

被引:51
作者
Yan, Zheng [1 ]
Liu, Huiqing [1 ]
Liu, Heguo [1 ]
机构
[1] Hubei Univ, Sch Math & Comp Sci, Wuhan 430062, Peoples R China
基金
中国国家自然科学基金;
关键词
Zagreb index; unicyclic graph; pendant vertex;
D O I
10.1007/s10910-006-9132-7
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
The second Zagreb index M-2( G) of a ( molecule) graph G is the sum of the weights d( u) d( v) of all edges uv of G, where d( u) denotes the degree of the vertex u. In this paper, we give sharp upper and lower bounds on the second Zagreb index of unicyclic graphs with n vertices and k pendant vertices. From which, U-n-3(n) and C-n have the maximum and minimum the second Zagreb index among all unicyclic graphs with n vertices, respectively.
引用
收藏
页码:565 / 574
页数:10
相关论文
共 14 条
[1]  
BALABAN AT, 1983, TOP CURR CHEM, V114, P21
[2]  
Bondy J.A., 1976, Graph Theory and Its Applications
[3]  
DAS KC, 2005, MATCH COMMUN MATH CO, V53, P103
[4]  
Gutman I, 2004, MATCH-COMMUN MATH CO, P83
[5]   GRAPH THEORY AND MOLECULAR-ORBITALS - TOTAL PI-ELECTRON ENERGY OF ALTERNANT HYDROCARBONS [J].
GUTMAN, I ;
TRINAJSTIC, N .
CHEMICAL PHYSICS LETTERS, 1972, 17 (04) :535-538
[6]   GRAPH THEORY AND MOLECULAR-ORBITALS .12. ACYCLIC POLYENES [J].
GUTMAN, I ;
RUSCIC, B ;
TRINAJSTIC, N ;
WILCOX, CF .
JOURNAL OF CHEMICAL PHYSICS, 1975, 62 (09) :3399-3405
[7]  
Kier L. H., 1976, Molecular Connectivity in Chemistry and Drug Research
[8]  
Kier L.H., 1986, Molecular Connectivity in Structure-Activity Analysis
[9]  
Liu BL, 2006, MATCH-COMMUN MATH CO, V55, P439
[10]  
Nikolic S, 2003, CROAT CHEM ACTA, V76, P113