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Related papers: Better bounds for poset dimension and boxicity

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The degree diameter problem asks for the maximum possible number of vertices in a graph of maximum degree $\Delta$ and diameter $D$. In this paper, we focus on planar graphs of diameter $3$. Fellows, Hell and Seyffarth (1995) proved that…

Combinatorics · Mathematics 2025-07-28 Antoine Dailly , Sasha Darmon , Ugo Giocanti , Claire Hilaire , Petru Valicov

An axis-parallel $d$-dimensional box is a cartesian product $I_1\times I_2\times \dots \times I_b$ where $I_i$ is a closed sub-interval of the real line. For a graph $G = (V,E)$, the $boxicity \ of \ G$, denoted by $\text{box}(G)$, is the…

Combinatorics · Mathematics 2021-05-07 Marco Caoduro , Lyuben Lichev

The boxicity of a graph is the smallest dimension $d$ allowing a representation of it as the intersection graph of a set of $d$-dimensional axis-parallel boxes. We present a simple general approach to determining the boxicity of a graph…

Combinatorics · Mathematics 2025-01-10 Marco Caoduro , András Sebő

Given a graph $G$, we would like to find (if it exists) the largest induced subgraph $H$ in which there are at least $k$ vertices realizing the maximum degree of $H$. This problem was first posed by Caro and Yuster. They proved, for…

Combinatorics · Mathematics 2017-04-28 Yair Caro , Josef Lauri , Christina Zarb

The boxicity of a graph is the smallest dimension $d$ allowing a representation of it as the intersection graph of a set of $d$-dimensional axis-parallel boxes. We present a simple general approach to determining the boxicity of a graph…

Combinatorics · Mathematics 2023-09-06 Marco Caoduro , András Sebő

Motivated by quite recent research involving the relationship between the dimension of a poset and graph-theoretic properties of its cover graph, we show that for every $d\geq 1$, if $P$ is a poset and the dimension of a subposet $B$ of $P$…

Combinatorics · Mathematics 2018-12-11 William T. Trotter , Bartosz Walczak , Ruidong Wang

A \emph{tree-partition} of a graph $G$ is a proper partition of its vertex set into `bags', such that identifying the vertices in each bag produces a forest. The \emph{tree-partition-width} of $G$ is the minimum number of vertices in a bag…

Combinatorics · Mathematics 2009-04-02 David R. Wood

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

An axis-parallel b-dimensional box is a Cartesian product $R_1 \times R_2 \times ... \times R_b$ where each $R_i$ (for $1 \leq i \leq b$) is a closed interval of the form $[a_i,b_i]$ on the real line. The boxicity of any graph $G$, box(G)…

Combinatorics · Mathematics 2007-05-23 L. Sunil Chandran , K. Ashik Mathew

A $k$-box $B=(R_1,...,R_k)$, where each $R_i$ is a closed interval on the real line, is defined to be the Cartesian product $R_1\times R_2\times ...\times R_k$. If each $R_i$ is a unit length interval, we call $B$ a $k$-cube. Boxicity of a…

Combinatorics · Mathematics 2012-01-31 Abhijin Adiga , L. Sunil Chandran , Rogers Mathew

The isolation number of a graph $G$ (also called the vertex-edge domination number of $G$), denoted by $\iota(G)$, is the size of a smallest subset $D$ of the vertex set $V(G)$ of $G$ such that $G-N[D]$ (the graph obtained by deleting the…

Combinatorics · Mathematics 2025-02-17 Peter Borg , Magdalena Lemańska , Mercè Mora , María José Souto-Salorio

The celebrated result of Koml\'os, S\'ark\"ozy, and Szemer\'edi states that for any $\varepsilon>0$, there exists $0<c<1$, such that for all sufficiently large $n$, every $n$-vertex graph $G$ with $\delta(G)\geq(1/2+\varepsilon)n$ contains…

Combinatorics · Mathematics 2025-10-21 Jun Yan

The Borodin--Kostochka conjecture states that every graph $G$ with maximum degree $\Delta(G)\ge 9$ satisfies $\chi(G)\le \max\{\omega(G),\Delta(G)-1\}$. In this paper, we verify this conjecture for graphs with sufficiently large maximum…

Combinatorics · Mathematics 2026-05-12 Feng Liu , Shuang Sun , Yan Wang , Jiasheng Zeng

The boxicity of a graph $G$ is the least integer $d$ such that $G$ has an intersection model of axis-aligned $d$-dimensional boxes. Boxicity, the problem of deciding whether a given graph $G$ has boxicity at most $d$, is NP-complete for…

Combinatorics · Mathematics 2014-02-21 Henning Bruhn , Morgan Chopin , Felix Joos , Oliver Schaudt

A proper $k$-colouring of a graph $G$ is called $h$-conflict-free if every vertex $v$ has at least $\min\, \{h, {\rm deg}(v)\}$ colours appearing exactly once in its neighbourhood. Let $\chi_{\rm pcf}^h(G)$ denote the minimum $k$ such that…

Combinatorics · Mathematics 2026-02-12 Quentin Chuet , Tianjiao Dai , Qiancheng Ouyang , François Pirot

The 'boxicity' ('cubicity') of a graph G is the minimum natural number k such that G can be represented as an intersection graph of axis-parallel rectangular boxes (axis-parallel unit cubes) in $R^k$. In this article, we give estimates on…

Combinatorics · Mathematics 2013-05-23 L. Sunil Chandran , Wilfried Imrich , Rogers Mathew , Deepak Rajendraprasad

We show that every graph $G$ of maximum degree $\Delta$ and sufficiently large order has a vertex cutset $S$ of order at most $\Delta$ that induces a subgraph $G[S]$ of maximum degree at most $\Delta-3$. For $\Delta\in \{ 4,5\}$, we refine…

Combinatorics · Mathematics 2023-04-21 Stéphane Bessy , Johannes Rauch , Dieter Rautenbach , Uéverton S. Souza

A classical result of Erd\H{o}s and Gallai determines the maximum size $m(n,\nu)$ of a graph $G$ of order $n$ and matching number $\nu n$. We show that $G$ has factorially many maximum matchings provided that its size is sufficiently close…

Combinatorics · Mathematics 2021-08-03 Stéphane Bessy , Johannes Pardey , Lucas Picasarri-Arrieta , Dieter Rautenbach

Erd\H{o}s, Pach, Pollack, and Tuza [\textit{J. Combin. Theory Ser. B, 47(1) (1989), 73-79}] proved that the diameter of a connected $n$-vertex graph with minimum degree $\delta$ is at most $\frac{3n}{\delta+1}+O(1)$. The oriented diameter…

Combinatorics · Mathematics 2025-04-15 Garner Cochran , Zhiyu Wang

The three well-known graph classes, planar graphs (P), series-parallel graphs(SP) and outer planar graphs(OP) satisfy the following proper inclusion relation: OP C SP C P. It is known that box(G) <= 3 if G belongs to P and box(G) <= 2 if G…

Combinatorics · Mathematics 2007-05-23 Ankur Bohra , L. Sunil Chandran , J. Krishnam Raju