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Related papers: Non-magic Hypergraphs

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A $d$-dimensional hypercube drawing of a graph represents the vertices by distinct points in $\{0,1\}^d$, such that the line-segments representing the edges do not cross. We study lower and upper bounds on the minimum number of dimensions…

Combinatorics · Mathematics 2007-05-23 David R. Wood

For a $k$-uniform hypergraph $\mathcal{H}$ on vertex set $\{1, ..., n\}$ we associate a particular signed incidence matrix $M(\mathcal{H})$ over the integers. For $\mathcal{H} \sim \mathcal{H}_k(n, p)$ an Erd\H{o}s--R\'{e}nyi random…

Combinatorics · Mathematics 2021-11-23 Andrew Newman

We study a model of random uniform hypergraphs, where a random instance is obtained by adding random edges to a large hypergraph of a given density. We obtain a tight bound on the number of random edges required to ensure…

Combinatorics · Mathematics 2007-07-04 Benny Sudakov , Jan Vondrak

We consider the notions of sum graph and of relaxed sum graph over a magma, give several examples and results of these families of graphs over some natural magmas. We classify the cycles that are sum graphs for the magma of the subsets of a…

Combinatorics · Mathematics 2024-01-19 António Machiavelo , Rogério Reis

We say that a $k$-uniform hypergraph $C$ is a Hamilton cycle of type $\ell$, for some $1\le \ell \le k$, if there exists a cyclic ordering of the vertices of $C$ such that every edge consists of $k$ consecutive vertices and for every pair…

Combinatorics · Mathematics 2010-03-10 Alan Frieze , Michael Krivelevich

For real application and theoretical investigation of ordinary hypergraphs and non-ordinary hypergraphs, researchers need to establish standard rules and feasible operating methods. We propose a visualization tool for investigating…

History and Overview · Mathematics 2025-03-27 Fei Ma , Bing Yao

I found a novel class of magic square analogue, magic 24-cell. The problem is to assign the consecutive numbers 1 through 24 to the vertices in a graph, which is composed of 24 octahedra and 24 vertices, to make the sum of the numbers of…

General Mathematics · Mathematics 2020-02-27 Donghwi Park

We say that a $k$-uniform hypergraph $C$ is a Hamilton cycle of type $\ell$, for some $1\le \ell \le k$, if there exists a cyclic ordering of the vertices of $C$ such that every edge consists of $k$ consecutive vertices and for every pair…

Combinatorics · Mathematics 2011-02-09 Deepak Bal , Alan Frieze

In this paper we focus on the problem of finding (small) subhypergraphs in a (large) hypergraph. We use this problem to illustrate that reducing hypergraph problems to graph problems by working with the 2-section is not always a reasonable…

We consider large uniform labeled random graphs in different classes with prescribed decorations in their modular decomposition. Our main result is the estimation of the number of copies of every graph as an induced subgraph. As a…

Combinatorics · Mathematics 2023-10-25 Théo Lenoir

A magic series is a set of natural numbers that, by virtue of its size, sum, and maximum value, could fill a row of a normal magic square. In this paper, we derive an exact two-dimensional integral representation for the number of magic…

Combinatorics · Mathematics 2013-06-05 Michael Quist

I present an algorithm that, given a number $n \geq 1$, computes a compact representation of the set of all noncrossing acyclic digraphs with $n$ nodes. This compact representation can be used as the basis for a wide range of dynamic…

Data Structures and Algorithms · Computer Science 2015-04-21 Marco Kuhlmann

A geometric graph is a graph whose vertices are points in general position in the plane and its edges are straight line segments joining these points. In this paper we give an $O(n^2 \log n)$ algorithm to compute the number of pairs of…

Computational Geometry · Computer Science 2020-09-04 Frank Duque , Ruy Fabila-Monroy , César Hernández-Vélez , Carlos Hidalgo-Toscano

A hypergraph is a $T_0$-hypergraph if for every two different vertices of the hypergraph there exists an edge containing one of the vertices and not containing the other. A general method for the enumeration of certain classes of…

Combinatorics · Mathematics 2014-11-18 Goran Kilibarda , Vladeta Jovović

We study several extensions of the notion of perfect graphs to $k$-uniform hypergraphs.

Combinatorics · Mathematics 2022-10-04 Maria Chudnovsky , Gil Kalai

We give a sharp bound for the automorphism group of a cubic simple graph with a given number of vertices. For each number of vertices we give an explicit graph attaining the bound, and prove its uniqueness in special cases.

Combinatorics · Mathematics 2007-05-23 Michael A. van Opstall , Razvan Veliche

A $k$-uniform hypergraph $M$ is set-homogeneous if it is countable (possibly finite) and whenever two finite induced subhypergraphs $U,V$ are isomorphic there is $g\in Aut(M)$ with $U^g=V$; the hypergraph $M$ is said to be homogeneous if in…

Logic · Mathematics 2022-02-22 Amir Assari , Narges Hosseinzadeh , Dugald Macpherson

In this paper we consider aspects of geometric observability for hypergraphs, extending our earlier work from the uniform to the nonuniform case. Hypergraphs, a generalization of graphs, allow hyperedges to connect multiple nodes and…

Dynamical Systems · Mathematics 2024-04-12 Joshua Pickard , Cooper Stansbury , Amit Surana , Indika Rajapakse , Anthony Bloch

A connected $k$-uniform hypergraph with $n$ vertices and $m$ edges is called $r$-cyclic if $n=m(k-1)-r+1$. For $r=1$ or $2$, the hypergraph is simply called unicyclic or bicyclic. In this paper we investigate hypergraphs that attain larger…

Combinatorics · Mathematics 2016-07-29 Chen Ouyang , Liqun Qi , Xiying Yuan

A hypermap is an embedding of a connected hypergraph into an orientable closed surface. A covering between hypermaps is a homomorphism between the embedded hypergraphs which extends to an orientation-preserving covering of the supporting…

Combinatorics · Mathematics 2018-06-13 Na-Er Wang , Kan Hu