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Related papers: Graphical distances & inertia

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A result of Bapat and Sivasubramanian gives the inertia of the distance squared matrix of a tree. We develop general tools on how pendant vertices and degree 2 vertices affect the inertia of the distance squared matrix and use these to give…

Combinatorics · Mathematics 2022-11-28 Christian Howell , Mark Kempton , Kellon Sandall , John Sinkovic

In this paper we propose and study a new structural invariant for graphs, called distance-unbalanced\-ness, as a measure of how much a graph is (un)balanced in terms of distances. Explicit formulas are presented for several classes of…

Combinatorics · Mathematics 2020-11-04 Štefko Miklavič , Primož Šparl

Let $G$ be a connected graph on $n$ vertices and $D(G)$ its distance matrix. The formula for computing the determinant of this matrix in terms of the number of vertices is known when the graph is either a tree or {a} unicyclic graph. In…

The \emph{distance matrix} of a simple connected graph $G$ is $D(G)=(d_{ij})$, where $d_{ij}$ is the distance between the vertices $i$ and $j$ in $G$. We consider a weighted tree $T$ on $n$ vertices with edge weights are square matrix of…

Combinatorics · Mathematics 2017-10-30 Fouzul Atik , M. Rajesh Kannan , R. B. Bapat

We establish maximal trees and graphs for the difference of average distance and proximity proving thus the corresponding conjecture posed in [4]. We also establish maximal trees for the difference of average eccentricity and remoteness and…

Combinatorics · Mathematics 2020-10-22 Jelena Sedlar

Let $G_w$ be a weighted graph. The \textit{inertia} of $G_w$ is the triple $In(G_w)=\big(i_+(G_w),i_-(G_w), $ $ i_0(G_w)\big)$, where $i_+(G_w),i_-(G_w),i_0(G_w)$ are the number of the positive, negative and zero eigenvalues of the…

Combinatorics · Mathematics 2013-07-02 Guihai Yu , Xiao-Dong Zhang , Lihua Feng

This paper introduces a new class of graphs, the CP graphs, and shows that their distance determinant and distance inertia are independent of their structures. The CP graphs include the family of linear $2$-trees. When a graph is attached…

Combinatorics · Mathematics 2018-05-28 Yen-Jen Cheng , Jephian C. -H. Lin

Let G be an undirected graph on n vertices and let S(G) be the set of all real symmetric n x n matrices whose nonzero off-diagonal entries occur in exactly the positions corresponding to the edges of G. The inverse inertia problem for G…

Combinatorics · Mathematics 2007-11-21 Wayne Barrett , H. Tracy Hall , Raphael Loewy

The number of the positive, negative and zero eigenvalues in the spectrum of the (edge)-weighted graph $G$ are called positive inertia index, negative inertia index and nullity of the weighted graph $G$, and denoted by $i_+(G)$, $i_-(G)$,…

Combinatorics · Mathematics 2013-07-22 Shuchao Li , Feifei Song

The eccentricity matrix of a connected graph $G$ is obtained from the distance matrix of $G$ by retaining the largest distances in each row and each column, and setting the remaining entries as $0$. In this article, a conjecture about the…

Combinatorics · Mathematics 2020-08-18 Iswar Mahato , R. Gurusamy , M. Rajesh Kannan , S. Arockiaraj

We present a simple iterative strategy for measuring the connection strength between a pair of vertices in a graph. The method is attractive in that it has a linear complexity and can be easily parallelized. Based on an analysis of the…

Discrete Mathematics · Computer Science 2009-09-24 Jie Chen , Ilya Safro

Two cycles are referred as disjoint if they have no common edges. In this paper, we will investigate the determinant of the distance matrix of a graph, giving a formula for the determinant of the distance matrix of a bicyclic graph whose…

Combinatorics · Mathematics 2013-08-13 Shi-Cai Gong , Ju-Li Zhang , Guang-Hui Xu

Distance well-defined graphs consist of connected undirected graphs, strongly connected directed graphs and strongly connected mixed graphs. Let $G$ be a distance well-defined graph, and let ${\sf D}(G)$ be the distance matrix of $G$.…

Combinatorics · Mathematics 2017-11-29 Hui Zhou , Qi Ding , Ruiling Jia

The reverse degree distance is a connected graph invariant closely related to the degree distance proposed in mathematical chemistry. We determine the unicyclic graphs of given girth, number of pendant vertices and maximum degree,…

Combinatorics · Mathematics 2011-07-13 Zhibin Du , Bo Zhou

For a vertex $v$ of a graph $G$, a spanning tree $T$ of $G$ is distance-preserving from $v$ if, for any vertex $w$, the distance from $v$ to $w$ on $T$ is the same as the distance from $v$ to $w$ on $G$. If two vertices $u$ and $v$ are…

Discrete Mathematics · Computer Science 2014-07-25 Toru Araki , Shingo Osawa , Takashi Shimizu

The walk distances in graphs are defined as the result of appropriate transformations of the $\sum_{k=0}^\infty(tA)^k$ proximity measures, where $A$ is the weighted adjacency matrix of a graph and $t$ is a sufficiently small positive…

Combinatorics · Mathematics 2012-03-06 Pavel Chebotarev

Rubei et. al., established results for the distance matrix of positive weighted Petersen graphs. Focusing on the properties of the distance matrix, we generalized positive weighted Petersen graphs results to Kneser graphs. We analyzed…

Combinatorics · Mathematics 2019-02-05 Joshua Steier , Luis Monterroso

The distance energy of a simple connected graph $G$ is defined as the sum of absolute values of its distance eigenvalues. In this paper, we mainly give a positive answer to a conjecture of distance energy of clique trees proposed by Lin,…

Combinatorics · Mathematics 2021-02-23 Ya-Lei Jin , Rui Gu , Xiao-Dong Zhang

A new class of distances for graph vertices is proposed. This class contains parametric families of distances which reduce to the shortest-path, weighted shortest-path, and the resistance distances at the limiting values of the family…

Combinatorics · Mathematics 2011-01-25 Pavel Chebotarev

Recently K.-G. Grosse-Erdmann and D. Papathanasiou described hypercyclic shifts in weighted spaces on directed trees. In this note we discuss several simple examples of graphs which are not trees, e.g., the lattice graphs, and study…

Functional Analysis · Mathematics 2024-09-10 Anton Baranov , Andrei Lishanskii , Dimitris Papathanasiou
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