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Related papers: On the Augmented Zagreb Index

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The arithmetic-geometric index is a newly proposed degree-based graph invariant in mathematical chemistry. We give a sharp upper bound on the value of this invariant for connected chemical graphs of given order and size and characterize the…

The authors Mili$\breve{c}$evi$\acute{c}$ et al. introduced the reformulated Zagreb indices, which is a generalization of classical Zagreb indices of chemical graph theory. In the paper, we characterize the extremal properties of the first…

Combinatorics · Mathematics 2014-06-30 Shengjin Ji , Xia Li , Yongke Qu

Let $\prod(G)$ be Multiplicative Zagreb index of a graph G. A connected graph is a cactus graph if and only if any two of its cycles have at most one vertex in common, which has been the interest of researchers in the filed of material…

Combinatorics · Mathematics 2016-07-19 Shaohui Wang , Bing Wei

We consider topological indices I that are sums of f(deg(u)) f(deg(v)), where {u,v} are adjacent vertices and f is a function. The Randi{\'c} connectivity index or the Zagreb group index are examples for indices of this kind. In earlier…

Combinatorics · Mathematics 2007-05-23 Boris Hollas

In the last forty years, many scientists used graph theory to develop mathematical models for analyzing structures and properties of various chemical compounds. In this paper, we will establish formulas and bounds for generalized first…

Combinatorics · Mathematics 2024-09-11 Sanju Vaidya , Jeff Chang

The aim of this paper is to obtain new sharp inequalities for a large family of topological indices, including the first variable Zagreb index $M_1^\alpha$, and to characterize the set of extremal graphs with respect to them. Our main…

Combinatorics · Mathematics 2018-06-07 Alvaro Martínez-Pérez , José M. Rodríguez

In chemical graph theory, caterpillar trees have been an appealing model to represent the molecular structures of benzenoid hydrocarbon. Meanwhile, topological index has been thought of as a powerful tool for modeling quantitative…

Probability · Mathematics 2021-02-26 Panpan Zhang , Xiaojing Wang

The paper discusses the edge hyper-Zagreb index of a graph, which is calculated by replacing vertex degrees with edge degrees. The degree of an edge is determined by adding up the degrees of the end vertices of the edge and subtracting 2.…

General Mathematics · Mathematics 2024-06-26 Z. Aliannejadi , S. Shafiee Alamoti

The Zagreb index of a hypergraph is defined as the sum of the squares of the degrees of its vertices. A connected $k$-uniform hypergraph with $n$ vertices and $m$ edges is called bicyclic if $n=m(k-1)-1$. In this paper, we determine the…

Combinatorics · Mathematics 2025-06-11 Hong Zhou , Changjiang Bu

The F-index of a graph is defined as the sum of cubes of the vertex degrees of the graph. This was introduced in 1972, in the same paper where the first and second Zagreb indices were introduced to study the structure-dependency of total…

Combinatorics · Mathematics 2015-11-23 Nilanjan De , Sk. Md. Abu Nayeem , Anita Pal

The first Zagreb index $M_{1}$ of a graph is defined as the sum of the square of every vertex degree, and the second Zagreb index $M_{2}$ of a graph is defined as the sum of the product of vertex degrees of each pair of adjacent vertices.…

Combinatorics · Mathematics 2020-06-02 Xiaocong He , Xiaobo He

For a graph $G$, the first multiplicative Zagreb index $\prod_1(G) $ is the product of squares of vertex degrees, and the second multiplicative Zagreb index $\prod_2(G) $ is the product of products of degrees of pairs of adjacent vertices.…

Combinatorics · Mathematics 2021-08-09 Shengjin Ji , Shaohui Wang , Tilahun Muche , Sakander Hayat

Let ${\mathcal G}_n$ be the set of class of graphs of order $n$. The first Zagreb index $M_1(G)$ is equal to the sum of squares of the degrees of the vertices, and the second Zagreb index $M_2(G)$ is equal to the sum of the products of the…

Combinatorics · Mathematics 2023-09-26 Batmend Horoldagva , Kinkar Chandra Das

For a (molecular) graph, the first multiplicative Zagreb index $\prod_1(G) $ is the product of the square of every vertex degree, and the second multiplicative Zagreb index $\prod_2(G) $ is the product of the products of degrees of pairs of…

Combinatorics · Mathematics 2017-04-25 Shaohui Wang

Let $\mathbb{G} = (\mathcal{V}, \mathcal{E})$ be a simple connected graph, where $\mathcal{V}$ and $\mathcal{E}$ denote the vertex and edge sets, respectively. The first Zagreb index is defined as $\mathcal{M}_{1}(\mathbb{G}) = \sum_{v \in…

General Mathematics · Mathematics 2025-08-08 Waqar Ali , Mohamad Nazri Bin Husin , Muhammad Faisal Nadeem , Muqaddas Jabin

We examine the quantity \[S(G) = \sum_{uv\in E(G)} \min(\text{deg } u, \text{deg } v)\] over sets of graphs with a fixed number of edges. The main result shows the maximum possible value of $S(G)$ is achieved by three different classes of…

Combinatorics · Mathematics 2018-01-09 Ashwin Sah , Mehtaab Sawhney

The second Zagreb index of a graph G is denoted by $M_2(G)=\sum_{uv\in E(G)}d(u)d(v)$. In this paper, we investigate properties of the extremal graphs with the maximum second Zagreb indices with given graphic sequences, in particular…

Combinatorics · Mathematics 2015-03-30 Wei-Gang Yuan , Xiao-Dong Zhang

Motivated by the recently introduced topological index, the Somber index, we define a new topological index of a graph in this paper, we call it Sombor coindex. The Sombor coindex is defined by considering analogous contributions from the…

Combinatorics · Mathematics 2022-09-21 Phanjoubam Chinglensana , Sainkupar Mn Mawiong

Topological indices are real numbers invariant under graph isomorphisms. Chromatic analogue of topological indices has been introduced recently in literature in 2017. Mainly, chromatic versions of Zagreb indices are studied lately. This…

General Mathematics · Mathematics 2018-10-09 Smitha Rose , Sudev Naduvath

Let $G=(V,E)$ be a simple connected graph and $d_i$ be the degree of its $i$th vertex. In a recent paper [J. Math. Chem. 46 (2009) 1369-1376] the first geometric-arithmetic index of a graph $G$ was defined as $$GA_1=\sum_{ij\in E}\frac{2…

Combinatorics · Mathematics 2016-11-15 J. M. Rodriguez , J. A. Rodriguez-Velazquez , J. M. Sigarreta