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Related papers: On multipartite Hajnal-Szemer\'edi theorems

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In this note we show the following strengthening of a multipartite version of the Hajnal--Szemer\'edi theorem. For an integer $r \ge 3$ and $\gamma > 0$, there exists a constant $C$ such that if $p\ge Cn^{-2/r}(\log n)^{1/{r \choose 2}}$…

Combinatorics · Mathematics 2023-11-03 Jie Han , Jie Hu , Donglei Yang

Let $q$ be a positve integer, and $G$ be a $q$-partite simple graph on $qn$ vertices, with $n$ vertices in each vertex class. Let $\delta={k_q \over k_q+1}$, where $k_q=q+O(\log{q})$. If each vertex of $G$ is adjacent to at least $\delta n$…

Combinatorics · Mathematics 2008-07-29 Bela Csaba

A perfect $K_t$-matching in a graph $G$ is a spanning subgraph consisting of vertex disjoint copies of $K_t$. A classic theorem of Hajnal and Szemer\'edi states that if $G$ is a graph of order $n$ with minimum degree $\delta(G) \ge…

Combinatorics · Mathematics 2013-01-01 Allan Lo , Klas Markström

A seminal result of Hajnal and Szemer\'{e}di states that if a graph $G$ with $n$ vertices has minimum degree $\delta(G) \ge (r-1)n/r$ for some integer $r \ge 2$, then $G$ contains a $K_r$-factor, assuming $r$ divides $n$. Extremal examples…

Combinatorics · Mathematics 2018-06-20 Rajko Nenadov , Yanitsa Pehova

Given integers $ n \ge k >l \ge 1 $ and a $k$-graph $F$ with $|V(F)|$ divisible by $n$, define $t_l^k(n,F)$ to be the smallest integer $d$ such that every $k$-graph $H$ of order $n$ with minimum $l$-degree $\delta_l(H) \ge d $ contains an…

Combinatorics · Mathematics 2014-03-25 Allan Lo , Klas Markström

The celebrated Hajnal-Szemer\'edi theorem gives the precise minimum degree threshold that forces a graph to contain a perfect K_k-packing. Fischer's conjecture states that the analogous result holds for all multipartite graphs except for…

Combinatorics · Mathematics 2015-09-15 Peter Keevash , Richard Mycroft

In this paper, we prove the asymptotic multipartite version of the Alon-Yuster theorem, which is a generalization of the Hajnal-Szemer\'edi theorem: If $k\geq 3$ is an integer, $H$ is a $k$-colorable graph and $\gamma>0$ is fixed, then, for…

Combinatorics · Mathematics 2017-05-24 Ryan R. Martin , Jozef Skokan

A classical result by Hajnal and Szemer\'edi from 1970 determines the minimal degree conditions necessary to guarantee for a graph to contain a $K_r$-factor. Namely, any graph on $n$ vertices, with minimum degree $\delta(G) \ge…

Combinatorics · Mathematics 2020-07-10 Charlotte Knierim , Pascal Su

For a subgraph $G$ of the blow-up of a graph $F$, we let $\delta^*(G)$ be the smallest minimum degree over all of the bipartite subgraphs of $G$ induced by pairs of parts that correspond to edges of $F$. In [Triangle-factors in a balanced…

Combinatorics · Mathematics 2021-03-18 Beka Ergemlidze , Theodore Molla

For a positive integer r>=2, a K_r-factor of a graph is a collection vertex-disjoint copies of K_r which covers all the vertices of the given graph. The celebrated theorem of Hajnal and Szemer\'edi asserts that every graph on n vertices…

Combinatorics · Mathematics 2013-04-26 József Balogh , Graeme Kemkes , Choongbum Lee , Stephen J. Young

Consider a host hypergraph $G$ which contains a spanning structure due to minimum degree considerations. We collect three results proving that if the edges of $G$ are sampled at the appropriate rate then the spanning structure still appears…

Combinatorics · Mathematics 2023-05-17 Huy Tuan Pham , Ashwin Sah , Mehtaab Sawhney , Michael Simkin

Let $k$ be a positive integer and let $G$ be a graph with vertex set $V(G)$. A subset $D \subseteq V(G)$ is a $k$-dominating set if every vertex outside $D$ is adjacent to at least $k$ vertices in $D$. The $k$-domination number…

Combinatorics · Mathematics 2020-05-27 Gülnaz Boruzanlı Ekinci , Csilla Bujtás

The $k$th power of a graph $G$, denoted $G^k$, has the same vertex set as $G$, and two vertices are adjacent in $G^k$ if and only if there exists a path between them in $G$ of length at most $k$. A $K_r$-factor in a graph is a spanning…

Combinatorics · Mathematics 2022-11-29 Ajit Diwan , Aniruddha Joshi

For $k \in \mathbb N$, Corr\'adi and Hajnal proved that every graph $G$ on $3k$ vertices with minimum degree $\delta(G) \ge 2k$ has a $C_3$-factor, i.e., a partitioning of the vertex set so that each part induces the 3-cycle $C_3$. Wang…

Combinatorics · Mathematics 2013-09-19 Andrzej Czygrinow , H. A. Kierstead , Theodore Molla

Given hypergraphs $F$ and $H$, an $F$-factor in $H$ is a set of vertex-disjoint copies of $F$ which cover all the vertices in $H$. Let $K^- _4$ denote the $3$-uniform hypergraph with $4$ vertices and $3$ edges. We show that for sufficiently…

Combinatorics · Mathematics 2015-09-10 Jie Han , Allan Lo , Andrew Treglown , Yi Zhao

We show that for any constant $\mu>0$ and $k\ge 3$, there exists $\alpha>0$ such that the following holds for sufficiently large $n \in \mathbb{N}$. If $G=(V_{1},\ldots,V_{k},E)$ is a spanning subgraph of the $n$-blow-up of $K_{k}$ with…

Combinatorics · Mathematics 2026-02-12 Xinyu He , Xiangxiang Nie , Donglei Yang

Let $G$ be a simple graph. The $k$-th neighborhood of a vertex subset $S \subseteq V(G)$, denoted $\Lambda^k(S)$, is the set of vertices that are adjacent to at least $k$ vertices in $S$. The $k$-th binding number $\beta^k(G)$ is defined as…

Combinatorics · Mathematics 2025-08-27 Guantao Chen , Mikhail Lavrov , Yuying Ma , Jennifer Vandenbussche , Hein van der Holst

A $K_r$-factor of a graph $G$ is a collection of vertex-disjoint $r$-cliques covering $V(G)$. We prove the following algorithmic version of the classical Hajnal--Szemer\'edi Theorem in graph theory, when $r$ is considered as a constant.…

Combinatorics · Mathematics 2026-03-02 Luyining Gan , Jie Han , Jie Hu

For a graph $G$ and $p\in[0,1]$, we denote by $G_p$ the random sparsification of $G$ obtained by keeping each edge of $G$ independently, with probability $p$. We show that there exists a $C>0$ such that if $p\geq C(\log n)^{1/3}n^{-2/3}$…

Given $k\ge 2$ and two $k$-graphs ($k$-uniform hypergraphs) $F$ and $H$, an $F$-factor in $H$ is a set of vertex disjoint copies of $F$ that together cover the vertex set of $H$. Lenz and Mubayi were first to study the $F$-factor problems…

Combinatorics · Mathematics 2026-02-02 Shumin Sun
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