Results 251 to 260 of about 39,052 (275)

Extremal Values of the General Harmonic Index and General Sum-Connectivity Index of f-Benzenoids

Polycyclic Aromatic Compounds, 2020
The general harmonic index and general sum-connectivity index are two degree-based topological indices which reflect certain structural features of organic molecules.
Qingfang Ye, Fengwei Li, Ruixuan Ye
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On the maximum general sum-connectivity index of trees with a fixed order and maximum degree

Discrete Mathematics, Algorithms and Applications, 2020
The general sum-connectivity index of a graph [Formula: see text], denoted by [Formula: see text], is defined as [Formula: see text], where [Formula: see text] is the edge connecting the vertices [Formula: see text], [Formula: see text] denotes the degree of the vertex [Formula: see text], and [Formula: see text] is a nonzero real number.
Shahzad Ahmed
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Atom-bond sum-connectivity index [PDF]

Journal of Mathematical Chemistry, 2022
Akbar Ali is partially supported by Scientific Research Deanship, University of Ha’il, Saudi Arabia, through Project Numbers RG-22 002 and RG-22 005. Boris Furtula and Izudin Redžepović gratefully acknowledge financial support of the Serbian Ministry of ...
Akbar Ali, Boris Furtula, Izudin Redžepović   +2 more
exaly   +2 more sources

On trees of a fixed maximum degree with extremal general atom-bond sum-connectivity index

Journal of Applied Mathematics and Computing
We consider general atom-bond sum-connectivity indices $ABS_l(G)$ for $1/2 \leq l \leq 1$ and study their values over all trees on a given number of vertices with a fixed maximum degree $\Delta $. We obtain both the minimum and the maximum values and characterize the corresponding trees.
Akbar Ali, Tomislav Doslic, Zahid Raza
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General ( α , 2 ) Path Sum Connectivity Index of Nanostructures

Journal of Corrosion and Materials
The general path sum connectivity index of a molecular graph, denoted as t χ α ( G ) , is defined for a graph G , where α is a positive real number and t is a positive integer. This index is expressed as: t χ α ( G ) = ∑ p t = v j 1 v j 2 … v j t + 1 ⊆ G [ d G ( v j 1 ) + d G ( v j 2 ) + ⋯ + d G ( v j t + 1 ) ] α , where p t represents a ...
M. Awais
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Minimizing the General Atom-Bond Sum-Connectivity Index of Unicyclic Graphs

Journal of applied mathematics and computing. International journal
This paper gives the characterization of those graphs that minimize the general atom- bond sum-connectivity index ABS ȷ among all fixed-order unicyclic graphs of a given maximum degree for 1 ≤ ȷ < 2. It is also proved that the cycle graph uniquely minimizes the aforementioned index in the class of all fixed-order unicyclic graphs.
Akbar Ali, T. Došlić, A. Alanazi, Taher S. Hassan, Adel A. Attiya   +4 more
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On general sum-connectivity index

Journal of Mathematical Chemistry, 2010
Bo Zhou, Nenad Trinajstić, Trinajstić Nenad   +2 more
exaly   +2 more sources

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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On the General Sum–Connectivity Co–Index of Graphs

2011
In this paper, a new molecular-structure descriptor, the general sum–connectivity co–index   is considered, which generalizes the first Zagreb co–index and the general sum– connectivity index of graph theory. We mainly explore the lower and upper bounds in terms of the order and size for this new invariant.
SU, G., XU, L.
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On General Sum-Connectivity Index of Benzenoid Systems and Phenylenes

2010
The general sum-connectivity index of a graph G, denoted by ) (G a a χ χ = is defined as ∑ ∈ + = ) ( ) ( G E uv a v u a d d χ , where du (or dv) is the degree of the vertex u (or v). Efficient formulas for calculating the general sum-connectivity index of benzenoid systems and their phenylenes are given, and a relation is established between the ...
CHEN, SH., XIA, F., YANG, J.
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