Minimum sum-connectivity indices of trees and unicyclic graphs of a given matching number

被引:67
作者
Du, Zhibin [1 ]
Zhou, Bo [1 ]
Trinajstic, Nenad [2 ]
机构
[1] S China Normal Univ, Dept Math, Guangzhou 510631, Guangdong, Peoples R China
[2] Rugjer Boskovic Inst, Zagreb 10002, Croatia
关键词
Randic connectivity index; Sum-connectivity index; Product-connectivity index; Trees; Unicyclic graphs; Matching number; RANDIC INDEX; TRENDS;
D O I
10.1007/s10910-009-9604-7
中图分类号
O6 [化学];
学科分类号
0703 ;
摘要
The sum-connectivity index is a newly proposed molecular descriptor defined as the sum of the weights of the edges of the graph, where the weight of an edge uv of the graph, incident to vertices u and v, having degrees d (u) and d (v) is (d (u) + d (v) )(-1/2). We obtain the minimum sum-connectivity indices of trees and unicyclic graphs with given number of vertices and matching number, respectively, and determine the corresponding extremal graphs. Additionally, we deduce the n-vertex unicyclic graphs with the first and second minimum sum-connectivity indices for n a parts per thousand yen 4.
引用
收藏
页码:842 / 855
页数:14
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