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Related papers: On a covering problem in the hypercube

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In their famous 1974 paper introducing the local lemma, Erd\H{o}s and Lov\'asz posed a question-later referred by Erd\H{o}s as one of his three favorite open problems: What is the minimum number of edges in an $r$-uniform, intersecting…

Combinatorics · Mathematics 2025-04-15 Matija Bucić , Vanshika Jain , Varun Sivashankar

Given an integer $1\leq j <n$, define the $(j)$-coloring of a $n$-dimensional hypercube $H_{n}$ to be the $2$-coloring of the edges of $H_{n}$ in which all edges in dimension $i$, $1\leq i \leq j$, have color $1$ and all other edges have…

Combinatorics · Mathematics 2017-08-10 Lina Xue , Weihua Yang , Shurong Zhang

Alon and F\"{u}redi (1993) showed that the number of hyperplanes required to cover $\{0,1\}^n\setminus \{0\}$ without covering $0$ is $n$. We initiate the study of such exact hyperplane covers of the hypercube for other subsets of the…

Combinatorics · Mathematics 2021-07-02 James Aaronson , Carla Groenland , Andrzej Grzesik , Tom Johnston , Bartłomiej Kielak

We consider a problem proposed by Linial and Wilf to determine the structure of graphs that allows the maximum number of $q$-colorings among graphs with $n$ vertices and $m$ edges. Let $T_r(n)$ denote the Tur\'{a}n graph - the complete…

Combinatorics · Mathematics 2022-09-21 Melissa M Fuentes

The Ramsey number $r_k(p, q)$ is the smallest integer $N$ that satisfies for every red-blue coloring on $k$-subsets of $[N]$, there exist $p$ integers such that any $k$-subset of them is red, or $q$ integers such that any $k$-subset of them…

Combinatorics · Mathematics 2019-07-31 S. Cliff Liu

How small can a set of vertices in the $n$-dimensional hypercube $Q_n$ be if it meets every copy of $Q_d$? The asymptotic density of such a set (for $d$ fixed and $n$ large) is denoted by $\gamma_d$. It is easy to see that $\gamma_d \leq…

Combinatorics · Mathematics 2025-07-11 David Ellis , Maria-Romina Ivan , Imre Leader

The discrete cube $\{0,1\}^d$ is a fundamental combinatorial structure. A subcube of $\{0,1\}^d$ is a subset of $2^k$ of its points formed by fixing $k$ coordinates and allowing the remaining $d-k$ to vary freely. The subcube structure of…

Combinatorics · Mathematics 2011-10-20 J. Robert Johnson , Klas Markström

We consider the following type of question: Given a partial proper $d$-edge coloring of the $d$-dimensional hypercube $Q_d$, and lists of allowed colors for the non-colored edges of $Q_d$,can we extend the partial coloring to a proper…

Combinatorics · Mathematics 2017-11-06 C. J Casselgren , K. Markström , L. A. Pham

This paper introduces a new variant of hypercubes, which we call Z-cubes. The n-dimensional Z-cube $H_n$ is obtained from two copies of the (n-1)-dimensional Z-cube $H_{n-1}$ by adding a special perfect matching between the vertices of…

Combinatorics · Mathematics 2015-09-24 Xuding Zhu

Graham, R\"odl, and Ruci\'nski originally posed the problem of determining the minimum number of monochromatic Schur triples that must appear in any 2-coloring of the first $n$ integers. This question was subsequently resolved independently…

Combinatorics · Mathematics 2026-04-28 Olaf Parczyk , Christoph Spiegel

Ruskey and Savage in 1993 asked whether every matching in a hypercube can be extended to a Hamiltonian cycle. A positive answer is known for perfect matchings, but the general case has been resolved only for matchings of linear size. In…

Discrete Mathematics · Computer Science 2023-06-22 Tomáš Dvořák

We introduce and study certain notions which might serve as substitutes for maximum density packings and minimum density coverings. A body is a compact connected set which is the closure of its interior. A packing $\cal P$ with congruent…

Metric Geometry · Mathematics 2009-09-25 Gabor Fejes Tóth , Greg Kuperberg , Włodzimierz Kuperberg

How many hyperplanes in $\mathbb{R}^n$ are needed in order to slice every edge of the $n$-dimensional hypercube with vertex set $\{\pm 1\}^n$? Here, we say that a hyperplane $H\subseteq \mathbb{R}^n$ slices an edge of the hypercube if it…

Combinatorics · Mathematics 2025-10-21 Lisa Sauermann , Zixuan Xu

Bousquet, Lochet and Thomass\'e recently gave an elegant proof that for any integer $n$, there is a least integer $f(n)$ such that any tournament whose arcs are coloured with $n$ colours contains a subset of vertices $S$ of size $f(n)$ with…

Combinatorics · Mathematics 2017-09-01 Laurent Beaudou , Luc Devroye , Gena Hahn

An almost $k$-cover of the hypercube $Q^n = \{0,1\}^n$ is a collection of hyperplanes that avoids the origin and covers every other vertex at least $k$ times. When $k$ is large with respect to the dimension $n$, Clifton and Huang…

Combinatorics · Mathematics 2023-06-14 Shagnik Das , Valjakas Djaljapayan , Yen-chi Roger Lin , Wei-Hsuan Yu

An asymmetric covering D(n,R) is a collection of special subsets S of an n-set such that every subset T of the n-set is contained in at least one special S with |S| - |T| <= R. In this paper we compute the smallest size of any D(n,1) for n…

Combinatorics · Mathematics 2014-09-18 David Applegate , E. M. Rains , N. J. A. Sloane

For $n\geq s> r\geq 1$ and $k\geq 2$, write $n \rightarrow (s)_{k}^r$ if every hyperedge colouring with $k$ colours of the complete $r$-uniform hypergraph on $n$ vertices has a monochromatic subset of size $s$. Improving upon previous…

Combinatorics · Mathematics 2024-03-26 Bruno Jartoux , Chaya Keller , Shakhar Smorodinsky , Yelena Yuditsky

First we consider families in the hypercube $Q_n$ with bounded VC dimension. Frankl raised the problem of estimating the number $m(n,k)$ of maximal families of VC dimension $k$. Alon, Moran and Yehudayoff showed that…

Combinatorics · Mathematics 2017-10-25 Jozsef Balogh , Tamas Meszaros , Adam Zsolt Wagner

Consider a hypergraph $H_n^d$ where the vertices are points of the $d$-dimensional combinatorial cube $n^d$ and the edges are all sets of $n$ points such that they are in one line. We study the structure of the group of automorphisms of…

Discrete Mathematics · Computer Science 2020-12-11 Pavel Dvořák , Tomáš Valla

Combining two classical notions in extremal combinatorics, the study of Ramsey-Tur\'an theory seeks to determine, for integers $m\le n$ and $p \leq q$, the number $\mathsf{RT}_p(n,K_q,m)$, which is the maximum size of an $n$-vertex…

Combinatorics · Mathematics 2025-08-19 Hong Liu , Christian Reiher , Maryam Sharifzadeh , Katherine Staden