Results 11 to 20 of about 3,238 (232)
Bound for vertex PI index in terms of simple graph parameters
Filomat, 2013 The vertex PI index is a distance-based molecular structure descriptor, that recently found numerouschemicalapplications. InthisletterweobtainalowerboundonthevertexPIindexofaconnected graph in terms of number of vertices, edges, pendent vertices, and clique number, and characterize the extremal graphs.
das, kinkar, Gutman, Ivan
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On the extremal graphs with respect to the vertex PI index
Applied Mathematics Letters, 2010 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Ilić, Aleksandar, Aleksandar Ilić
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On trees and the multiplicative sum Zagreb index
Communications in Combinatorics and Optimization, 2016 For a graph $G$ with edge set $E(G)$, the multiplicative sum Zagreb index of $G$ is defined as $\Pi^*(G)=\Pi_{uv\in E(G)}[d_G(u)+d_G(v)]$, where $d_G(v)$ is the degree of vertex $v$ in $G$.
M. Eliasi, A. Ghalavand
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Scientific ReportsIn the fields of mathematics, chemistry, and the physical sciences, graph theory plays a substantial role. Using modern mathematical techniques, quantitative structure-property relationship (QSPR) modeling predicts the physical, synthetic, and natural ...
Sakander Hayat +5 more
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On extremal trees with respect to the F-index
Kuwait Journal of Science, 2017 In a study on the structure--dependency of the total $\pi$-electron energy from 1972,Trinajsti\'c and one of the present authors have shown that it depends on the sums$\sum_{v\in V}d(v)^2$ and $\sum_{v\in V}d(v)^3$, where $d(v)$ is the degree of a vertex
Hosam Abdo, Darko Dimitrov, Ivan Gutman
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Vertex PI Index and Szeged Index of Certain Special Molecular Graphs [PDF]
The Open Biotechnology Journal, 2014 The vertex PI index and Szeged index are distance-based topological index which reflect certain structural features of organic molecules. Each structural feature of such organic molecule can be expressed as a graph. In this paper, we determine the vertex PI index and Szeged index of fan molecular graph, wheel molecular graph, gear fan molecular graph ...
Li Yan, Junsheng Li, Wei Gao
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Bounds on Szeged and PI Indexes in terms of Second Zagreb Index [PDF]
, 2012 In this short note, we studied the vertex version and the edge version of the Szeged index and the PI index and obtained bounds for these indices in terms of the Second Zagreb index.
Ranjini P.S. +2 more
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Mathematical and Computer Modelling, 2013 Abstract The vertex PI index is a distance-based molecular structure descriptor, that recently found numerous chemical applications. In order to increase diversity of this topological index for bipartite graphs, we introduce a weighted version defined as P I w ( G ) = ∑ e = u v ∈ E ( d e g ( u ) + d e g (
Aleksandar Ilic, Nikola Milosavljevic
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Computation of edge Pi index, vertex Pi index and Szeged index of some cactus chains
Mathematica Montisnigri, 2022 A cactus chain is a connected graph in which all blocks are cycles, each cycle has at most two cut-vertices and each cut-vertex is shared by exactly two cycles. In this paper we give exact values of edge PI index and vertex PI index of an arbitrary cactus chain and vertex Szeged index of some special types of cactus chains.
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Vertex PI v Topological Index of Titania Carbon Nanotubes TiO 2 (m,n) [PDF]
Applied Mathematics and Nonlinear Sciences, 2016 Abstract A topological index of a graph G is a numeric quantity related to G which is invariant under automorphisms of G. The Padmakar-Ivan (PI) index of a graph G is defined as PI (
Mohammad Reza Farahani +2 more
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