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Related papers: On Certain Topological Indices of Signed Graphs

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Topological indices play an important role in mathematical chemistry especially in the quantitative structure-property relationship (QSPR) and quantitative structure-activity relationship (QSAR). Recent research indicates that the augmented…

Combinatorics · Mathematics 2016-07-26 Akbar Ali , Zahid Raza , Akhlaq Ahmad Bhatti

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

In this paper, the investigates Adriatic indices, specifically the sum lordeg index where it defined as $SL(G) = \sum_{u \in V(G)} \deg_G(u) \sqrt{\ln \deg_G(u)}$ and the variable sum exdeg index $SEI_a(G)$ for $a>0$, $a\neq 1$. We present…

Combinatorics · Mathematics 2025-08-07 Jasem Hamoud , Duaa Abdullah

For a graph $G$, the first multiplicative Zagreb index $\prod_1$ is equal to the product of squares of the vertex degrees, and the second multiplicative Zagreb index $\prod_2$ is equal to the product of the products of degrees of pairs of…

Combinatorics · Mathematics 2016-11-21 Shaohui Wang , Chunxiang Wang , Jia-Bao Liu

We determine the degree sequence of the generalized Sierpinski graph and its general first Zagreb index in terms of the same parameters of the base graph G.

Combinatorics · Mathematics 2019-01-23 Ali Behtoei , Fatemeh Attarzadeh , Mahsa Khatibi

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

A signed bipartite graph G(U, V) is a bipartite graph in which each edge is assigned a positive or a negative sign. The signed degree of a vertex x in G(U, V) is the number of positive edges incident with x less the number of negative edges…

Combinatorics · Mathematics 2007-05-23 S. Pirzada , T. A. Naikoo , F. A. Dar

The Wiener index is defined as the sum of distances between all unordered pairs of vertices in a graph. It is one of the most recognized and well-researched topological indices, which is on the other hand still a very active area of…

Combinatorics · Mathematics 2023-03-22 Martin Knor , Riste Škrekovski , Aleksandra Tepeh

Topological indices have important role in theoretical chemistry for QSPR researches. Among the all topological indices the Randi\'c and the Zagreb indices have been used more considerably than any other topological indices in chemical and…

Combinatorics · Mathematics 2017-01-12 Süleyman Ediz

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

In this paper, we investigate the structural properties of trees and bipartite graphs through the lens of topological indices and combinatorial graph theory. We focus on the First and Second Hyper-Zagreb indices, $HM_1(G)$ and $HM_2(G)$,…

Combinatorics · Mathematics 2025-08-21 Jasem Hamoud

A signed graph $ (G, \Sigma)$ is a graph positive and negative ($\Sigma $ denotes the set of negative edges). To re-sign a vertex $v$ of a signed graph $ (G, \Sigma)$ is to switch the signs of the edges incident to $v$. If one can obtain $…

Combinatorics · Mathematics 2016-04-01 Sandip Das , Soumen Nandi , Soumyajit Paul , Sagnik Sen

A signed graph is a graph whose edges are labeled either positive or negative. Corresponding to the two signed distance matrices defined for signed graphs, we define two signed distance laplacian matrices. We characterize balance in signed…

Combinatorics · Mathematics 2020-10-12 Roshni T Roy , K A Germina , K Shahul Hameed , Thomas Zaslavsky

A signed graph is a graph whose edges are labelled positive or negative. The sign of a circle (cycle, circuit) is the product of the signs of its edges. Most of the essential properties of a signed graph depend on the signs of its circles.…

Combinatorics · Mathematics 2021-06-16 Thomas Zaslavsky

Let $D=(V,A)$ be a digraphs without isolated vertices. A vertex-degree based invariant $I(D)$ related to a real function $\varphi$ of $D$ is defined as a summation over all arcs, $I(D) = \frac{1}{2}\sum_{uv\in A}{\varphi(d_u^+,d_v^-)}$,…

Combinatorics · Mathematics 2021-05-03 Hanyuan Deng , Jiaxiang Yang , Zikai Tang , Jing Yang , Meiling You

The set D of distinct signed degrees of the vertices in a signed graph G is called its signed degree set. In this paper, we prove that every non-empty set of positive (negative) integers is the signed degree set of some connected signed…

Combinatorics · Mathematics 2007-05-23 S. Pirzada , T. A. Naikoo , F. A. Dar

F-index of a graph is the sum of the cube of the degrees of the vertices. In this paper, we investigate the F-indices of unicyclic graphs by introducing some transformation, and characterize the unicyclic graphs with the first five largest…

Combinatorics · Mathematics 2016-09-06 Ruhul Amin , Sk. Md. Abu Nayeem

A signed graph $G$ is a graph where each edge is assigned a + (positive edge) or a - (negative edge). The signed degree of a vertex $v$ in a signed graph, denoted by $sdeg(v)$, is the number of positive edges incident to $v$ subtracted by…

Combinatorics · Mathematics 2021-09-06 Alvaro Carbonero , Janelle Domantay , Karen Guthrie

An extension of the well-known Szeged index was introduced recently, named as weighted Szeged index ($\textrm{sz}(G)$). This paper is devoted to characterizing the extremal trees and graphs of this new topological invariant. In particular,…

Combinatorics · Mathematics 2019-01-16 Jan Bok , Boris Furtula , Nikola Jedličková , Riste Škrekovski

Let $G$ be a group and $L(G)$ be the set of all subgroups of $G$. The subgroup generating bipartite graph $\mathcal{B}(G)$ defined on $G$ is a bipartite graph whose vertex set is partitioned into two sets $G \times G$ and $L(G)$, and two…

Group Theory · Mathematics 2025-01-13 Shrabani Das , Ahmad Erfanian , Rajat Kanti Nath
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