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Related papers: Note on PI and Szeged indices

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Causal discovery aims to recover graphs that represent causal relations among given variables from observations, and new methods are constantly being proposed. Increasingly, the community raises questions about how much progress is made,…

Machine Learning · Computer Science 2025-10-30 Zhufeng Li , Niki Kilbertus

We introduce the \emph{ID-index} of a finite simple connected graph. For a graph $G=(V,\ E)$ with diameter $d$, we let $f:V\longrightarrow \mathbb{R}$ assign \emph{ranks} to the vertices, then under $f$, each vertex $v$ gets a…

Combinatorics · Mathematics 2024-10-10 Runze Wang

Hansen et. al. used the computer programm AutoGraphiX to study the differences between the Szeged index $Sz(G)$ and the Wiener index $W(G)$, and between the revised Szeged index $Sz^*(G)$ and the Wiener index for a connected graph $G$. They…

Combinatorics · Mathematics 2012-12-10 Lily Chen , Xueliang Li , Mengmeng Liu

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. Rodríguez

We make use of multiplicative degree-based topological indices $X_\Pi(G)$ to perform a detailed analytical and statistical study of random networks $G=(V(G),E(G))$. We consider two classes of indices: $X_\Pi(G) = \prod_{u \in V(G)}…

Combinatorics · Mathematics 2023-06-06 R. Aguilar-Sanchez , J. A. Mendez-Bermudez , Jose M. Rodriguez , Jose M. Sigarreta

This work introduces the development of path Dirac and hypergraph Dirac operators, along with an exploration of their persistence. These operators excel in distinguishing between harmonic and non-harmonic spectra, offering valuable insights…

Algebraic Topology · Mathematics 2023-12-05 Faisal Suwayyid , Guo-Wei Wei

We consider infinite graphs. The distinguishing number $D(G)$ of a graph $G$ is the minimum number of colours in a vertex colouring of $G$ that is preserved only by the trivial automorphism. An analogous invariant for edge colourings is…

Combinatorics · Mathematics 2021-05-18 Wilfried Imrich , Rafał Kalinowski , Monika Pilśniak , Mohammad H. Shekarriz

Foucaud, Krishna and Lekshmi recently introduced the concept of monitoring edge-geodetic sets in graphs, and a related graph invariant. These are sets of vertices such that the removal of any edge changes the distance between some pair of…

Combinatorics · Mathematics 2023-07-20 John Haslegrave

Graphs are ubiquitous data structures for representing interactions between entities. With an emphasis on the use of graphs to represent chemical molecules, we explore the task of learning to generate graphs that conform to a distribution…

Machine Learning · Computer Science 2019-03-08 Qi Liu , Miltiadis Allamanis , Marc Brockschmidt , Alexander L. Gaunt

Let $G=(V,E)$ be a graph and $e=uv\in E$. Define $n_u(e,G)$ be the number of vertices of $G$ closer to $u$ than to $v$. The number $n_v(e,G)$ can be defined in an analogous way. The Mostar index of $G$ is a new graph invariant defined as…

Combinatorics · Mathematics 2021-06-15 Nima Ghanbari , Saeid Alikhani

For a graph $G$ with vertex set $V_{G}$ and edge set $E_{G}$, the symmetric division deg index is defined as $SDD(G)=\sum\limits_{uv\in E_{G}}(\frac{d_{u}}{d_{v}}+\frac{d_{v}}{d_{u}})$, where $d_{u}$ denotes the degree of vertex $u$ in $G$.…

Combinatorics · Mathematics 2022-07-12 Hechao Liu , Yufei Huang

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

An important application of distance geometry to biochemistry studies the embeddings of the vertices of a weighted graph in the three-dimensional Euclidean space such that the edge weights are equal to the Euclidean distances between…

Computational Geometry · Computer Science 2011-03-08 Leo Liberti , Carlile Lavor , Benoit Masson , Antonio Mucherino

We study topological Poincar\'e type inequalities on general graphs. We characterize graphs satisfying such inequalities and then turn to the best constants in these inequalities. Invoking suitable metrics we can interpret these constants…

Functional Analysis · Mathematics 2018-01-30 Daniel Lenz , Marcel Schmidt , Peter Stollmann

The first multiplicative Zagreb index of a graph $G$ is the product of the square of every vertex degree, while the second multiplicative Zagreb index is the product of the degree of each edge over all edges. In our work, we explore the…

Combinatorics · Mathematics 2017-04-28 Chunxiang Wang , Jia-Bao Liu , Shaohui Wang

Let $G = (V, E)$ be a graph. The first Zagreb index of a graph $G$ is defined as $\sum_{u \in V} d^2(u)$, where $d(u)$ is the degree of vertex $u$ in $G$. Using the P\'{o}lya-Szeg\H{o} inequality, we in this paper present the first Zagreb…

Combinatorics · Mathematics 2024-09-05 Rao Li

The structural analysis of shape boundaries leads to the characterization of objects as well as to the understanding of shape properties. The literature on graphs and networks have contributed to the structural characterization of shapes…

Computer Vision and Pattern Recognition · Computer Science 2017-11-15 Gisele H. B. Miranda , Jeaneth Machicao , Odemir M. Bruno

Graph vertex ordering is widely employed in spatial data analysis, especially in urban analytics, where street graphs serve as spatial discretization for modeling and simulation. It is also crucial for visualization, as many methods require…

Graphics · Computer Science 2025-10-23 Karelia Salinas , Victor Barella , Thales Viera , Luis Gustavo Nonato

The aim of this work is to obtain new inequalities for the variable symmetric division deg index $SDD_\alpha(G) = \sum_{uv \in E(G)} (d_u^\alpha/d_v^\alpha+d_v^\alpha/d_u^\alpha)$, and to characterize graphs extremal with respect to them.…

Combinatorics · Mathematics 2021-06-03 R. Aguilar-Sanchez , J. A. Mendez-Bermudez , Jose M. Rodriguez , Jose M. Sigarreta

Topological indices are a class of numerical invariants that predict certain physical and chemical properties of molecules. Recently, two novel topological indices, named as Sombor index and reduced Sombor index, were introduced by Gutman,…

Combinatorics · Mathematics 2021-08-24 Hechao Liu , Lihua You , Yufei Huang