Results 241 to 250 of about 4,436,056 (266)

Sharp lower bounds on the sum-connectivity index of trees

Discrete Mathematics, Algorithms and Applications, 2021
The sum-connectivity index of a graph [Formula: see text] is defined as the sum of weights [Formula: see text] over all edges [Formula: see text] of [Formula: see text], where [Formula: see text] and [Formula: see text] are the degrees of the vertices [Formula: see text] and [Formula: see text] in [Formula: see text], respectively. In this paper, some
S. Alyar, R. Khoeilar
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On the Maximum Atom-Bond Sum-Connectivity Index of Trees

MATCH – Communications in Mathematical and in Computer Chemistry, 2023
Topological indices have been under study since 1947 when H. Wiener proposed a mathematical formula to order the boiling temperatures of isomers of alkanes. Since then, over 3000 similar mathematical formulae have been defined and studied by mathematicians, chemists and by other scientists.
Hu, Yarong, Wang, Fangxia
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RELATION BETWEEN GENERAL RANDIC INDEX AND ´ GENERAL SUM CONNECTIVITY INDEX

South East Asian J. of Mathematics and Mathematical Sciences, 2022
The general Randi´c index is the sum of weights of (d(u).d(v))k for every edge uv of a molecular graph G. On the other hand general Sum-Connectivity index is the sum of the weights (d(u) + d(v))k for every edge uv of G, where k is a real number and d(u) is the degree of vertex u.
V. S., Shigehalli, Dsouza, Austin Merwin
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On general sum-connectivity index

Journal of Mathematical Chemistry, 2009
We report some properties especially lower and upper bounds in terms of other graph invariants for the general sum-connectivity index which generalizes both the ordinary sum-connectivity index and the first Zagreb index. Additionally, we give the Nordhaus-Gaddum-type result for the general sum-connectivity index.
Zhou, Bo, Trinajstić, Nenad
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The sum-connectivity index--an additive variant of the Randic connectivity index.

Current computer-aided drug design, 2013
This review discusses structure-property modeling applications of a novel variant of the Randic connectivity index that is called the sum-connectivity index. We compare published one-descriptor quantitative structure-property relationship (QSPR) models obtained with the new sum-connectivity index and with the Randic connectivity index, called here the ...
Lučić, Bono, Sović, Ivan, Batista, Jadranko, Skala, Karolj, Plavšić, Dejan, Vikić-Topić, Dražen, Bešlo, Drago, Nikolić, Sonja, Trinajstić, Nenad   +8 more
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Two-tree graphs with maximum general sum-connectivity index

Discrete Mathematics, Algorithms and Applications, 2020
For a simple graph [Formula: see text], the general sum-connectivity index is defined as [Formula: see text], where [Formula: see text] is the degree of the vertex [Formula: see text] and [Formula: see text] is a real number. In this paper, we will obtain sharp upper bounds on the general sum-connectivity index for [Formula: see text].
R. Khoeilar, H. Shooshtari
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A Variant of Atom Bond Sum Connectivity Index

Match Communications in Mathematical and in Computer Chemistry
Summary: Topological index is a numerical graph invariant derived from molecular graph. The atom bond sum connectivity index drew a lot of interest from chemical graph theorists in a short period of time. Nowadays, the degree sum of a vertex's first neighbors is recognized as a useful parameter in chemical graph theory. Keeping these two facts in mind,
Yasin H, Mohammed, M, Suresh, Mondal, Sourav   +2 more
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Two-tree graphs with minimum sum-connectivity index

Discrete Mathematics, Algorithms and Applications, 2020
The sum-connectivity index of a graph [Formula: see text] is defined as the sum of weights [Formula: see text] over all edges [Formula: see text] of [Formula: see text], where [Formula: see text] and [Formula: see text] are the degrees of the vertices [Formula: see text] and [Formula: see text] in [Formula: see text], respectively.
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Progress in general sum-connectivity index

2011 International Conference on Electronics, Communications and Control (ICECC), 2011
The general sum-connectivity index of a graph G is defined as χ a (G) = Σ uv∊E(G) (d u +d v )α, where d u (or d v ) denotes the degree of vertex u (or v) in G, E(G) denotes the edge set of G, and α is a real number. This paper outlines the results up to now on this problem.
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On the general sum-connectivity index of tricyclic graphs

Journal of Applied Mathematics and Computing, 2015
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Zhu, Zhongxun, Lu, Hongyan
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