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Related papers: Note on PI and Szeged indices

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In this paper, we examine a specific type of random chains and propose an unified approach to studying the degree-based topological indices, including their extreme values. We derive explicit analytical expressions for the expected values…

Probability · Mathematics 2024-11-08 Sayle Sigarreta , Hugo Cruz-Suarez , Sergio Torralbas Fitz

In this paper, we present a dynamic programming approach for identifying extremal polyomino chains with respect to degree-based topological indices. This approach provides an explicit recurrence and constructive algorithm that enables both…

Combinatorics · Mathematics 2025-09-16 Manuel Montes-y-Morales , Saylé Sigarreta , Hugo Cruz-Suárez

There are various topological indices for example distance based topological indices and degree based topological indices etc. In QSAR/QSPR study, physiochemical properties and topological indices for example atom bond connectivity index,…

Discrete Mathematics · Computer Science 2018-04-26 Raghisa Khalid , Nazeran Idrees

Making use of a majorization technique for a suitable class of graphs, we derive upper and lower bounds for some topological indices depending on the degree sequence over all vertices, namely the first general Zagreb index and the first…

Combinatorics · Mathematics 2015-03-27 Monica Bianchi , Alessandra Cornaro , José Luis Palacios , Anna Torriero

In this paper extremal values of the difference between several graph invariants related to the metric dimension are studied: mixed metric dimension, edge metric dimension and strong metric dimension. These non-trivial extremal values are…

Combinatorics · Mathematics 2020-12-15 Milica Milivojević Danas

Applications in chemistry motivated mathematicians to define different topological indices for different types of graphs. The Hyper-Zagreb index (HM) is an important tool as it integrates the first and the second Zagreb indices. In this…

Combinatorics · Mathematics 2018-09-12 Hassan Rezapour , Ramin Nasiri , Seyedahmad Mousavi

Many existing degree based topological indices can be classified as bond incident degree (BID) indices, whose general form is $BID(G)=\sum_{uv\in E(G)}$ $\Psi(d_{u},d_{v})$, where $uv$ is the edge connecting the vertices $u,v$ of the graph…

Combinatorics · Mathematics 2018-03-14 Akbar Ali , Darko Dimitrov

Topological indices are scientific details of graphs which represents its topology and of the most part graph invariant. In QSAR/QSPR, physico-chemical characteristics and topological indices, for example, atom bond connectivity (ABC) and…

Combinatorics · Mathematics 2019-10-24 Haidar Ali , Farzana Kousar

Let $\mathcal{H}$ be a hypergraph on the non-empty finite vertex set $V(\mathcal{H})$ with the hyperedge set $E(\mathcal{H})$, where each hyperedge $e \in E(\mathcal{H})$ is a subset of $V(\mathcal{H})$ with at least two vertices. This…

Discrete Mathematics · Computer Science 2025-09-18 Abdulkafi Sanad

We perform a detailed statistical study of the distribution of topological and spectral indices on random graphs $G=(V,E)$ in a wide range of connectivity regimes. First, we consider degree-based topological indices (TIs), and focus on two…

Combinatorics · Mathematics 2026-02-23 C. T. Martínez-Martínez , R. Aguilar-Sánchez , J. A. Méndez-Bermúdez

The revised Szeged index of a graph $G$ is defined as $Sz^*(G)=\sum_{e=uv \in E}(n_u(e)+ n_0(e)/2)(n_v(e)+ n_0(e)/2),$ where $n_u(e)$ and $n_v(e)$ are, respectively, the number of vertices of $G$ lying closer to vertex $u$ than to vertex…

Combinatorics · Mathematics 2013-07-02 Lily Chen , Xueliang Li , Mengmeng Liu

Quantitative Structure-Property Relationship (QSPR) analysis plays a crucial role in predicting physicochemical properties and biological activities of pharmaceutical compounds, aiding in drug design and optimization. This study focuses on…

Biomolecules · Quantitative Biology 2025-03-21 Sezer Sorgun , Kahraman Birgin

The distance $d(u,v)$ between the vertices $u$ and $v$ of a connected graph $G$ is defined as the number of edges in a minimal path connecting them. The \emph{transmission} of a vertex $v$ of $G$ is defined by $\sigma(v)=\sum\limits_{u\in…

Combinatorics · Mathematics 2018-09-18 Reza Sharafdini , Tamas Reti

The concept of geometric-arithmetic index was introduced in the chemical graph theory recently, but it has shown to be useful. The aim of this paper is to obtain new inequalities involving the geometric-arithmetic index $GA_1$ and…

Combinatorics · Mathematics 2017-03-17 Alvaro Martínez-Pérez , José M. Rodríjuez , José M. Sigarreta

Very recently, the first geometric-arithmetic index $GA$ and arithmetic-geometric index $AG$ were introduced in mathematical chemistry. In the present paper, we first obtain some lower and upper bounds on $AG$ and characterize the extremal…

Combinatorics · Mathematics 2020-10-09 Shu-Yu Cui , Weifan Wang , Gui-Xian Tian , Baoyindureng Wu

Obtaining consistent explanations for machine learning on molecular graphs requires predictions and attributions to be aligned with chemical identity. However, chemically equivalent drawings of the same molecule can induce different…

Machine Learning · Computer Science 2026-05-26 Emanuele Guidotti , Sara Puglioli

Measures of the irregularity of chemical graphs could be helpful for QSAR/QSPR studies and for the descriptive purposes of biological and chemical properties, such as melting and boiling points, toxicity and resistance. Here we consider the…

Discrete Mathematics · Computer Science 2016-08-19 Hosam Abdo , Darko Dimitrov , Wei Gao

Let $G = (V, E)$ be a graph. The first Zagreb index and the forgotten topological index of a graph $G$ are defined respectively as $\sum_{u \in V} d^2(u)$ and $\sum_{u \in V} d^3(u)$, where $d(u)$ is the degree of vertex $u$ in $G$. If the…

Combinatorics · Mathematics 2024-09-23 Rao Li

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…

Discrete Mathematics · Computer Science 2015-09-21 Hosam Abdo , Darko Dimitrov , Ivan Gutman

A topological index reflects the physical, chemical and structural properties of a molecule, and its study has an important role in molecular topology, chemical graph theory and mathematical chemistry. It is a natural problem to…

Combinatorics · Mathematics 2022-07-08 Rui Song , Qiongxiang Huang