Some new bounds on the general sum–connectivity index

Let $G=(V,E)$ be a simple connected graph with $n$ vertices, $m$ edges and sequence of vertex degrees $d_1 \ge d_2 \ge \cdots \ge d_n>0$, $d_i=d(v_i)$, where $v_i\in V$. With $i\sim j$ we denote adjacency of vertices $v_i$ and $v_j$. The general sum--connectivity index of graph is defined as...

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Bibliographic Details
Main Authors: Akbar Ali, Mubeen Javaid, Marjan Matejic, Igor Milovanovic, Emina Milovanovic
Format: Article
Language:English
Published: Azarbaijan Shahide Madani University 2020-12-01
Series:Communications in Combinatorics and Optimization
Subjects:
Online Access:http://comb-opt.azaruniv.ac.ir/article_13987_683b3467bb550bc427ec378858c86a80.pdf
Description
Summary:Let $G=(V,E)$ be a simple connected graph with $n$ vertices, $m$ edges and sequence of vertex degrees $d_1 \ge d_2 \ge \cdots \ge d_n>0$, $d_i=d(v_i)$, where $v_i\in V$. With $i\sim j$ we denote adjacency of vertices $v_i$ and $v_j$. The general sum--connectivity index of graph is defined as $\chi_{\alpha}(G)=\sum_{i\sim j}(d_i+d_j)^{\alpha}$, where $\alpha$ is an arbitrary real number. In this paper we determine relations between $\chi_{\alpha+\beta}(G)$ and $\chi_{\alpha+\beta-1}(G)$, where $\alpha$ and $\beta$ are arbitrary real numbers, and obtain new bounds for $\chi_{\alpha}(G)$. Also, by the appropriate choice of parameters $\alpha$ and $\beta$, we obtain a number of old/new inequalities for different vertex--degree--based topological indices.
ISSN:2538-2128
2538-2136