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Related papers: Equidistant dimension of Johnson and Kneser graphs

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Some graphs admit drawings in the Euclidean k-space in such a (natu- ral) way, that edges are represented as line segments of unit length. Such drawings will be called k dimensional unit distance representations. When two non-adjacent…

Combinatorics · Mathematics 2010-01-07 Jan Kratochvil , Boris Horvat , Tomaz Pisanski

This is a chapter in a forthcoming book on completely regular codes in distance regular graphs. The chapter provides an overview, and some original results, on codes in distance regular graphs which admit symmetries via a permutation group…

Combinatorics · Mathematics 2024-07-16 Daniel R. Hawtin , Cheryl E. Praeger

In the $m$-dimensional affine space $AG(m,q)$ over the finite field $\mathbb{F}_q$ of odd order $q$, the analogous of the Euclidean distance gives rise to a graph $\mathfrak{G}_{m,q}$ where vertices are the points of $AG(m,q)$ and two…

Combinatorics · Mathematics 2021-02-08 Gábor Korchmáros , Federico Romaniello , Tamás Szőnyi

We classify the maximal $m$-distance sets in $\mathbb{R}^{n-1}$ which contain the representation of the Johnson graph $J(n, m)$ for $m = 2, 3$. Furthermore, we determine the necessary and sufficient condition for $n$ and $m$ such that the…

Combinatorics · Mathematics 2012-09-04 Eiichi Bannai , Takahiro Sato , Junichi Shigezumi

Let $G$ be a simple and connected graph with vertex set $V(G)$. A vertex $w\in V(G)$ strongly resolves two vertices $u,v \in V(G)$ if $v$ belongs to a shortest $u-w$ path or $u$ belongs to a shortest $v-w$ path. A set $W \subseteq V(G)$ is…

Combinatorics · Mathematics 2019-05-13 Rashid Farooq , Naila Mehreen

Comparability graphs are graphs which have transitive orientations. The dimension of a poset is the least number of linear orders whose intersection gives this poset. The dimension ${\rm dim}(X)$ of a comparability graph $X$ is the…

Discrete Mathematics · Computer Science 2015-06-17 Pavel Klavík , Peter Zeman

The metric dimension of a graph $G$ is the minimum number of vertices in a subset $S$ of the vertex set of $G$ such that all other vertices are uniquely determined by their distances to the vertices in $S$. In this paper we investigate the…

Combinatorics · Mathematics 2014-06-12 B. Bollobas , D. Mitsche , P. Pralat

Consider two simple graphs, G1 and G2, with their respective vertex sets V(G1) and V(G2). The Kronecker product forms a new graph with a vertex set V(G1) X V(G2). In this new graph, two vertices, (x, y) and (u, v), are adjacent if and only…

Spectral Theory · Mathematics 2024-12-02 Priti Prasanna Mondal , Fouzul Atik

The generalized Kneser graph $K(n,k,t)$ for integers $k>t>0$ and $n>2k-t$ is the graph whose vertices are the $k$-subsets of $\{1,\dots,n\}$ with two vertices adjacent if and only if they share less than $t$ elements. We determine the…

Combinatorics · Mathematics 2022-03-29 Klaus Metsch

We show that for the attractor $(K_{1},\dots,K_{q})$ of a graph directed iterated function system, for each $1\leq j\leq q$ and $\varepsilon>0$ there exits a self-similar set $K\subseteq K_{j}$ that satisfies the strong separation condition…

Dynamical Systems · Mathematics 2018-10-17 Ábel Farkas

A generator of a metric space is a set $S$ of points in the space with the property that every point of the space is uniquely determined by its distances from the elements of $S$. Given a simple graph $G=(V,E)$, we define the distance…

Combinatorics · Mathematics 2015-10-21 A. Estrada-Moreno , Y. Ramirez-Cruz , J. A. Rodriguez-Velazquez

The Kn\"odel graph $W_{\Delta,n}$ is a $\Delta$-regular bipartition graph on $n\ge 2^{\Delta}$ vertices and $n$ is an even integer. The vertices of $W_{\Delta,n}$ are the pairs $(i,j)$ with $i=1,2$ and $0\le j\le n/2-1$. For every $j$,…

Combinatorics · Mathematics 2026-04-08 Seyed Reza Musawi , Esameil Nazari Kiashi

We consider the localization number and metric dimension of certain graphs of diameter $2$, focusing on families of Kneser graphs and graphs without 4-cycles. For the Kneser graphs with diameter $2$, we find upper and lower bounds for the…

Combinatorics · Mathematics 2020-08-12 Anthony Bonato , Melissa A. Huggan , Trent Marbach

The metric dimension is quite a well-studied graph parameter. Recently, the adjacency dimension and the local metric dimension have been introduced and studied. In this paper, we give a general formula for the local metric dimension of the…

In a graph $G$, a geodesic between two vertices $x$ and $y$ is a shortest path connecting $x$ to $y$. A subset $S$ of the vertices of $G$ is in general position if no vertex of $S$ lies on any geodesic between two other vertices of $S$. The…

Combinatorics · Mathematics 2019-07-23 Balázs Patkós

The size sz(G) of an l_1-graph G=(V,E) is the minimum of n_f/t_f over all its possible l_1-embeddings f into n_f-dimensional hypercube with scale t_f. In terms of v=|V|, the sum of distances between all the pairs of vertices of G is at most…

Combinatorics · Mathematics 2007-05-23 Michel Deza , Dmitrii V. Pasechnik

A connected graph $G$ of diameter ${\rm diam}(G) \ge \ell$ is $\ell$-distance-balanced if $|W_{xy}|=|W_{yx}|$ for every $x,y\in V(G)$ with $d_{G}(x,y)=\ell$, where $W_{xy}$ is the set of vertices of $G$ that are closer to $x$ than to $y$.…

Combinatorics · Mathematics 2025-12-10 Gang Ma , Jianfeng Wang , Sandi Klavžar

For a finite simple graph $G$, say $G$ is of dimension $n$, and write $\dim(G) = n$, if $n$ is the smallest integer such that $G$ can be represented as a unit-distance graph in $\mathbb{R}^n$. Define $G$ to be \emph{dimension-critical} if…

Combinatorics · Mathematics 2023-03-30 Matt Noble

We study equitable 2-partitions of the Johnson graphs J(n,w) with a quotient matrix containing the eigenvalue lambda_2(w,n) = (w-2)(n-w-2)-2 in its spectrum. For any w>=4 and n>=2w, we find all admissible quotient matrices of such…

Combinatorics · Mathematics 2020-03-25 Konstantin Vorob'ev

Let $G$ be a connected graph with $V(G)=\{v_1,\ldots,v_n\}$. The $(i,j)$-entry of the distance matrix $D(G)$ of $G$ is the distance between $v_i$ and $v_j$. In this article, using the well-known Ramsey's theorem, we prove that for each…

Combinatorics · Mathematics 2022-03-07 Ezequiel Dratman , Luciano N. Grippo , Verónica Moyano , Adrián Pastine
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