On acyclic and unicyclic conjugated graphs with maximum Zagreb indices

被引:0
作者
Li, Shuchao [1 ]
Zhao, Qin [1 ]
机构
[1] Cent China Normal Univ, Fac Math & Stat, Wuhan 430079, Peoples R China
基金
美国国家科学基金会;
关键词
Zagreb indices; Tree; Unicyclic graph; Perfect matching; m-matching; RANDIC INDEX; MOLECULAR-ORBITALS; 2ND-ZAGREB INDEX; TREES; BOUNDS; SQUARES; SUM;
D O I
暂无
中图分类号
O29 [应用数学];
学科分类号
070104 ;
摘要
For a molecular graph, the first Zagreb index M-1 is equal to the sum of squares of the vertex degrees, and the second Zagreb index M-2 is equal to the sum of products of degrees of pairs of adjacent vertices. In this paper, we first obtain a sharp upper bound on M-1-values of trees in terms of the order and the given size of matching. Then we investigate Zagreb indices of unicyclic conjugated graphs G (i.e., unicyclic graphs with a perfect matching) and a sharp upper bound on M-1(G), M-2(G) are determined, respectively. The sharp upper bounds for Zagreb indices of unicyclic graphs in terms of the order and given size of matching are also determined.
引用
收藏
页码:115 / 128
页数:14
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