摘要
图G的第三Zagreb指标和第三版Zagreb指标分别是M3(G)=∑uv∈E(G)|d(u)-d(v)|,M′1(G)=∑u∈V(G)dG(u)δG(u).该文研究了树型结构分子图的两类Zagreb指标.更准确地说,得到了一个随机选择的树型结构的n阶分子图的两类Zagreb指标的平均值和方差的界.
The third Zagreb index and the third version of Zagreb indices of a graph G are M3(G)=∑uv∈E(G)|d(u)-d(v)| and M′1(G)=∑u∈V(G)dG(u)δG(u) respectively.In this paper,we study the two Zagreb indices of molecular graph with tree structure.More precisely,we obtain the bounds for the average and variance of two indices in a randomly chosen molecular graph with tree structure of order n.
引文
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