Results 21 to 30 of about 10,946,765 (186)
The Third Leap Zagreb Index for Trees
Journal of Chemistry, 2019 The third leap Zagreb index is the sum of the products of vertex degrees and second degrees. In this paper, a lower bound on the third leap Zagreb index is established, and the extremal trees achieving this bound are characterized.
Jia-Ming Zhu +2 more
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Alexandria Engineering Journal, 2023 Introduced by Gutman & Trinajstić in 1972, the two well-known Zagreb indices efficiently determine the total π-electron energy of alternant hydrocarbons. The hyper-Zagreb index is a variant of the classical first Zagreb index.
Sakander Hayat +4 more
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The Second Hyper-Zagreb Coindex of Chemical Graphs and Some Applications
Journal of Chemistry, 2021 The second hyper-Zagreb coindex is an efficient topological index that enables us to describe a molecule from its molecular graph. In this current study, we shall evaluate the second hyper-Zagreb coindex of some chemical graphs. In this study, we compute
Ahmed Ayache +3 more
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Tetracyclic graphs with maximum second Zagreb index: A simple approach
Asian-European Journal of Mathematics, 2018 In the chemical graph theory, graph invariants are usually referred to as topological indices. The second Zagreb index (denoted by [Formula: see text]) is one of the most studied topological indices.
Akbar Ali
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Exponential second Zagreb index of connected graphs [PDF]
Discrete Mathematics LettersBatmend Horoldagva +2 more
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On the Reformulated Second Zagreb Index of Graph Operations [PDF]
Journal of Chemistry, 2021 Topological indices (TIs) are expressed by constant real numbers that reveal the structure of the graphs in QSAR/QSPR investigation. The reformulated second Zagreb index (RSZI) is such a novel TI having good correlations with various physical attributes, chemical reactivities, or biological activities/properties.
Durbar Maji +2 more
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On a conjecture about the second Zagreb index [PDF]
Discrete Mathematics Letters, 2019 Summary: The cyclomatic number \(\nu\) of a graph \(G\) is the minimum number of those edges of \(G\) whose removal makes \(G\) acyclic. The second Zagreb index \(M_2\) for a graph \(G\) is the sum of the products of degrees of adjacent vertices of \(G\).
Kinkar Chandra Das, Akbar Ali
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Trees with the minimal second Zagreb index [PDF]
Kragujevac Journal of Mathematics, 2018 Summary: For simple graph \(G\) with edge set \(E(G)\), the second Zagreb index of \(G\) is defined as \(M_2(G)=\sum_{uv\in E(G)}[d_G(u)d_G(v)]\), where \(d_G(v)\) is the degree of the vertex \(v\) in \(G\). In this paper, we identify the nine classes of trees, which have the first to the sixth smallest second Zagreb indices, among all the trees of the
Eliasi, M., Ghalav, A.
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Upper bounds for the reduced second Zagreb index of graphs
Transactions on Combinatorics, 2021 Summary: The graph invariant \(RM_2\), known under the name reduced second Zagreb index, is defined as \(RM_2(G)=\sum_{uv \in E(G)}(d_G(u)-1)(d_G(v)-1)\), where \(d_G(v)\) is the degree of the vertex \(v\) of the graph \(G\). In this paper, we give a tight upper bound of \(RM_2\) for the class of graphs of order \(n\) and size \(m\) with at least one ...
Horoldagva, Batmend +3 more
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Second Zagreb index of trees with fixed diameter [PDF]
Scientific Publications of the State University of Novi Pazar Series A: Applied Mathematics, Informatics and mechanics, 2020 Let G be a simple graph with vertex set V = V(G) = {v1, v2,..., vn} and edge set E = E(G). For vi ∈ V(G), by di = di(G) we denote the degree (number of neighbors) of the vertex vi. The second Zagreb index is defined as M2(G) = ∑ vivj∈E(G) didj. In this paper, we study the minimal and maximal second Zagreb index of trees with fixed diameter.
E.H. Zogić, E.R. Glogić
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