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Related papers: On the irregularity of uniform hypergraphs

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The concept of a hyperuniformity disorder length $h$ was recently introduced for analyzing volume fraction fluctuations for a set of measuring windows. This length permits a direct connection to the nature of disorder in the spatial…

Soft Condensed Matter · Physics 2017-09-20 D. J. Durian

Let $\mathcal{U}(n,k)$ and $\Gamma(n,k)$ be the set of the $k$-uniform linear and nonlinear unicyclic hypergraphs having perfect matchings with $n$ vertices respectively, where $n\geq k(k-1)$ and $k\geq 3$. By using some techniques of…

Combinatorics · Mathematics 2022-03-01 Rui Sun , Wen-Huan Wang , Zhen-Yu Ni

The "infamous upper tail problem" for $r$-uniform hypergraphs is to estimate the probability that the number of copies of a fixed hypergraph $H$ in a large binomial $r$-uniform hypergraph $\boldsymbol{G}$ exceeds its expectation by a…

Combinatorics · Mathematics 2025-10-01 Nicholas A. Cook , Nguyen Nguyen

Let $m:=|E(G)|$ sufficiently large and $s:=(m-1)/3$. We show that unless the maximum degree $\Delta > 2s$, there is a weighting $w:E\cup V\to \{0,1,...,s\}$ so that $w(uv)+w(u)+w(v)\ne w(u'v')+w(u')+w(v')$ whenever $uv\ne u'v'$ (such a…

Combinatorics · Mathematics 2010-06-24 Florian Pfender

Given a sequence of $s$-uniform hypergraphs $\{H_n\}_{n \geq 1}$, denote by $T_p(H_n)$ the number of edges in the random induced hypergraph obtained by including every vertex in $H_n$ independently with probability $p \in (0, 1)$. Recent…

Probability · Mathematics 2019-04-02 Somabha Mukherjee , Bhaswar B. Bhattacharya

For all integers $k,d$ such that $k \geq 3$ and $k/2\leq d \leq k-1$, let $n$ be a sufficiently large integer {\rm(}which may not be divisible by $k${\rm)} and let $s\le \lfloor n/k\rfloor-1$. We show that if $H$ is a $k$-uniform hypergraph…

Combinatorics · Mathematics 2022-08-16 Yulin Chang , Huifen Ge , Jie Han , Guanghui Wang

An oriented hypergraph is a hypergraph where each vertex-edge incidence is given a label of $+1$ or $-1$. The adjacency and Laplacian eigenvalues of an oriented hypergraph are studied. Eigenvalue bounds for both the adjacency and Laplacian…

Combinatorics · Mathematics 2015-06-18 Nathan Reff

Let $H$ and $G$ be two finite graphs. Define $h_H(G)$ to be the number of homomorphisms from $H$ to $G$. The function $h_H(\cdot)$ extends in a natural way to a function from the set of symmetric matrices to $\mathbb{R}$ such that for…

Functional Analysis · Mathematics 2008-06-03 Hamed Hatami

A hypergraph $H$ is called universal for a family $\mathcal{F}$ of hypergraphs, if it contains every hypergraph $F \in \mathcal{F}$ as a copy. For the family of $r$-uniform hypergraphs with maximum vertex degree bounded by $\Delta$ and at…

Combinatorics · Mathematics 2016-05-16 Samuel Hetterich , Olaf Parczyk , Yury Person

We revisit the problem of designing sublinear algorithms for estimating the average degree of an $n$-vertex graph. The standard access model for graphs allows for the following queries: sampling a uniform random vertex, the degree of a…

Data Structures and Algorithms · Computer Science 2025-10-24 Lorenzo Beretta , Deeparnab Chakrabarty , C. Seshadhri

The \textit{domination number} $\gamma(\mathcal{H})$ of a hypergraph $\mathcal{H}=(V(\mathcal{H}),E(\mathcal{H})$ is the minimum size of a subset $D\subset V(\mathcal{H}$ of the vertices such that for every $v\in V(\mathcal{H})\setminus D$…

Combinatorics · Mathematics 2016-07-19 Csilla Bujtás , Balázs Patkós , Zsolt Tuza , Máté Vizer

A transversal coalition in a hypergraph $H$ is a partition of the vertex set $U$ into two subsets $U_1$ and $U_2$ such that neither $U_1$ nor $U_2$ alone intersects every hyperedge of $H$, but their union, $U_1 \cup U_2$, intersects every…

Combinatorics · Mathematics 2026-03-03 Vrushali Shinde , Lata Kadam

We investigate extremal problems for quasirandom hypergraphs. We say that a $3$-uniform hypergraph $H=(V,E)$ is $(d,\eta)$-quasirandom if for any subset $X\subseteq V$ and every set of pairs $P\subseteq V\times V$ the number of pairs…

Combinatorics · Mathematics 2016-09-20 Christian Reiher , Vojtěch Rödl , Mathias Schacht

The Erd\H{o}s--Hajnal Theorem asserts that non-universal graphs, that is, graphs that do not contain an induced copy of some fixed graph $H$, have homogeneous sets of size significantly larger than one can generally expect to find in a…

Combinatorics · Mathematics 2018-05-22 Michal Amir , Asaf Shapira , Mykhaylo Tyomkyn

We investigate bootstrap percolation with infection threshold $r> 1$ on the binomial $k$-uniform random hypergraph $H_k(n,p)$ in the regime $n^{-1}\ll n^{k-2}p \ll n^{-1/r}$, when the initial set of infected vertices is chosen uniformly at…

Combinatorics · Mathematics 2017-04-25 Mihyun Kang , Christoph Koch , Tamás Makai

We study notions of hyperuniformity for invariant locally square-integrable point processes in regular trees. We show that such point processes are never geometrically hyperuniform, and if the diffraction measure has support in the…

Probability · Mathematics 2024-09-18 Mattias Byléhn

For a $d$-uniform random hypergraph on $n$ vertices in which hyperedges are included i.i.d.\ so that the average degree in the hypergraph is $n^{\delta+o(1)}$, the projection of such a hypergraph is a graph on the same $n$ vertices where an…

Statistics Theory · Mathematics 2026-04-03 Shuyang Gong , Zhangsong Li , Qiheng Xu

For an $r$-uniform hypergraph $H$, let $\nu^{(m)}(H)$ denote the maximum size of a set~$M$ of edges in $H$ such that every two edges in $M$ intersect in less than $m$ vertices, and let $\tau^{(m)}(H)$ denote the minimum size of a collection…

Combinatorics · Mathematics 2022-10-25 Abdul Basit , Daniel McGinnis , Henry Simmons , Matt Sinnwell , Shira Zerbib

Fix an integer $k \ge 3$. A $k$-uniform hypergraph is simple if every two edges share at most one vertex. We prove that there is a constant $c$ depending only on $k$ such that every simple $k$-uniform hypergraph $H$ with maximum degree $\D$…

Combinatorics · Mathematics 2008-09-21 Alan Frieze , Dhruv Mubayi

An ordered hypergraph is a hypergraph whose vertex set is linearly ordered, and a convex geometric hypergraph is a hypergraph whose vertex set is cyclically ordered. Extremal problems for ordered and convex geometric graphs have a rich…

Combinatorics · Mathematics 2019-06-12 Zoltán F\" uredi , Tao Jiang , Alexandr Kostochka , Dhruv Mubayi , Jacques Verstraëte