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Related papers: Lower Bounds for Boxicity

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Two boxes in $\mathbb{R}^d$ are comparable if one of them is a subset of a translation of the other one. The comparable box dimension of a graph $G$ is the minimum integer $d$ such that $G$ can be represented as a touching graph of…

Discrete Mathematics · Computer Science 2022-03-16 Zdenek Dvorák , Daniel Goncalves , Abhiruk Lahiri , Jane Tan , Torsten Ueckerdt

The boxicity of a graph G, denoted as box(G) is defined as the minimum integer t such that G is an intersection graph of axis-parallel t-dimensional boxes. A graph G is a k-leaf power if there exists a tree T such that the leaves of the…

Combinatorics · Mathematics 2009-02-23 L. Sunil Chandran , Mathew C. Francis , Rogers Mathew

In this short note, we relate the boxicity of graphs (and the dimension of posets) with their generalized coloring parameters. In particular, together with known estimates, our results imply that any graph with no $K_t$-minor can be…

Combinatorics · Mathematics 2019-01-21 Louis Esperet , Veit Wiechert

Let $H$, $T$ and $C_n$ be a graph, a tree and a cycle of order $n$, respectively. Let $H^{(i)}$ be the complete join of $H$ and an empty graph on $i$ vertices. Then the Cartesian product $H\Box T$ of $H$ and $T$ can be obtained by applying…

Combinatorics · Mathematics 2023-04-06 Xiwu Yang , Xiaodong Cheng , Yuansheng Yang

We define and study a class of graphs, called 2-stab interval graphs (2SIG), with boxicity 2 which properly contains the class of interval graphs. A 2SIG is an axes-parallel rectangle intersection graph where the rectangles have unit height…

Discrete Mathematics · Computer Science 2016-04-01 Sujoy Kumar Bhore , Dibyayan Chakraborty , Sandip Das , Sagnik Sen

A unit cube in $k$ dimensions ($k$-cube) is defined as the the Cartesian product $R_1\times R_2\times...\times R_k$ where $R_i$(for $1\leq i\leq k$) is a closed interval of the form $[a_i,a_i+1]$ on the real line. A graph $G$ on $n$ nodes…

Discrete Mathematics · Computer Science 2008-03-27 L. Sunil Chandran , Mathew C. Francis , Naveen Sivadasan

Let $G(V,E)$ be a simple, undirected graph where $V$ is the set of vertices and $E$ is the set of edges. A $b$-dimensional cube is a Cartesian product $I_1\times I_2\times...\times I_b$, where each $I_i$ is a closed interval of unit length…

Combinatorics · Mathematics 2009-03-09 Abhijin Adiga , L. Sunil Chandran

In this paper we study Cartesian products of graphs and their divisorial gonality, which is a tropical version of the gonality of an algebraic curve. We present an upper bound on the gonality of the Cartesian product of any two graphs, and…

Combinatorics · Mathematics 2019-09-24 Ivan Aidun , Ralph Morrison

The outer multiset dimension ${\rm dim}_{\rm ms}(G)$ of a graph $G$ is the cardinality of a smallest set of vertices that uniquely recognize all the vertices outside this set by using multisets of distances to the set. It is proved that…

Combinatorics · Mathematics 2022-07-15 Sandi Klavzar , Dorota Kuziak , Ismael G. Yero

For a set W of vertices and a vertex v in a graph G, the k-vector r2(v|W) = (aG(v,w1),...,aG(v,wk)) is the adjacency representation of v with respect to W, where W = {w1,...,wk} and aG(x,y) is the minimum of 2 and the distance between the…

Combinatorics · Mathematics 2021-03-02 Mohsen Jannesari

In this short note, we prove the following analog of the K\H{o}v\'ari-S\'os-Tur\'an theorem for intersection graphs of boxes. If $G$ is the intersection graph of $n$ axis-parallel boxes in $\mathbb{R}^{d}$ such that $G$ contains no copy of…

Combinatorics · Mathematics 2020-09-10 István Tomon , Dmitriy Zakharov

A family $\mathcal{F}$ of permutations of the vertices of a hypergraph $H$ is called 'pairwise suitable' for $H$ if, for every pair of disjoint edges in $H$, there exists a permutation in $\mathcal{F}$ in which all the vertices in one edge…

An identifying code in a graph is a dominating set that also has the property that the closed neighborhood of each vertex in the graph has a distinct intersection with the set. The minimum cardinality of an identifying code, or ID code, in…

Combinatorics · Mathematics 2016-02-15 Douglas F. Rall , Kirsti Wash

A unit cube in $k$ dimensional space (or \emph{$k$-cube} in short) is defined as the Cartesian product $R_1\times R_2\times...\times R_k$ where $R_i$(for $1\leq i\leq k$) is a closed interval of the form $[a_i,a_i+1]$ on the real line. A…

Discrete Mathematics · Computer Science 2008-03-26 L. Sunil Chandran , Mathew C. Francis , Naveen Sivadasan

We study Hamiltonicity in graphs obtained as the union of a deterministic $n$-vertex graph $H$ with linear degrees and a $d$-dimensional random geometric graph $G^d(n,r)$, for any $d\geq1$. We obtain an asymptotically optimal bound on the…

Combinatorics · Mathematics 2022-09-29 Alberto Espuny Díaz

We introduce the notion of \emph{stab number} and \emph{exact stab number} of rectangle intersection graphs, otherwise known as graphs of boxicity at most 2. A graph $G$ is said to be a \emph{$k$-stabbable rectangle intersection graph}, or…

Discrete Mathematics · Computer Science 2018-04-23 Dibyayan Chakraborty , Mathew C. Francis

Let X \subset R be a bounded set; we introduce a formula that calculates the upper graph box dimension of X (i.e.the supremum of the upper box dimension of the graph over all uniformly continuous functions defined on X). We demonstrate the…

Classical Analysis and ODEs · Mathematics 2019-02-13 Vaios Laschos , Giorgos Kelgiannis

We give a complete description of the set of triples (a,b,c) of real numbers with the following property. There exists a constant K such that a n_3 + b n_2 + c n_1 - K is a lower bound for the matching number of every connected subcubic…

Combinatorics · Mathematics 2016-05-17 Penny Haxell , Alex Scott

By extending the definition of boxicity, we extend a Helly-type result given by Danzer and Grumbaum on 2-piercings of family of boxes in $d$-dimensional Euclidian space by lowering the dimension of the boxes in the ambient space.

Combinatorics · Mathematics 2018-01-26 Hector Baños , Déborah Oliveros

An obstacle representation of a graph $G$ is a set of points in the plane representing the vertices of $G$, together with a set of polygonal obstacles such that two vertices of $G$ are connected by an edge in $G$ if and only if the line…

Combinatorics · Mathematics 2017-07-18 Martin Balko , Josef Cibulka , Pavel Valtr