For a graph G,the first leap Zagreb index is defined as LM_(1)(G)=∑_(ν∈V(G))d_(2)(v/G)^(2),where d_(2)(v/G) is the 2-distance degree of a vertex v in G.Let QT^(k)(n) be the set of kgeneralized quasi-trees with n ve...For a graph G,the first leap Zagreb index is defined as LM_(1)(G)=∑_(ν∈V(G))d_(2)(v/G)^(2),where d_(2)(v/G) is the 2-distance degree of a vertex v in G.Let QT^(k)(n) be the set of kgeneralized quasi-trees with n vertices.In this paper,we determine the extremal elements from the set QT^(k)(n) with respect to the first leap Zagreb index.展开更多
基金Supported by the Foundation of Henan Department of Science and Technology(Grant No.182102310830)the Foundation of Henan University of Engineering(Grant No.D2016018)+1 种基金the Foundation of Henan Educational Committee(Grant Nos.20A1100162020GGJS239)。
文摘For a graph G,the first leap Zagreb index is defined as LM_(1)(G)=∑_(ν∈V(G))d_(2)(v/G)^(2),where d_(2)(v/G) is the 2-distance degree of a vertex v in G.Let QT^(k)(n) be the set of kgeneralized quasi-trees with n vertices.In this paper,we determine the extremal elements from the set QT^(k)(n) with respect to the first leap Zagreb index.
