English
Related papers

Related papers: An Improved Threshold for the Minimum Degree Krusk…

200 papers

Dirac (1952) proved that every connected graph of order $n>2k+1$ with minimum degree more than $k$ contains a path of length at least $2k+1$. Erd\H{o}s and Gallai (1959) showed that every $n$-vertex graph $G$ with average degree more than…

Combinatorics · Mathematics 2024-06-18 Yue Ma , Xinmin Hou , Jun Gao

A uniform hypergraph $H$ is called $k$-Ramsey for a hypergraph $F$, if no matter how one colors the edges of $H$ with $k$ colors, there is always a monochromatic copy of $F$. We say that $H$ is minimal $k$-Ramsey for $F$, if $H$ is…

Combinatorics · Mathematics 2015-02-05 Dennis Clemens , Yury Person

A tree $T$ in an edge-colored graph is a {\it proper tree} if no two adjacent edges of $T$ receive the same color. Let $G$ be a connected graph of order $n$ and $k$ be a fixed integer with $2\le k\le n$. For a vertex subset $S \subseteq…

Combinatorics · Mathematics 2016-03-30 Hong Chang , Xueliang Li , Zhongmei Qin

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

We provide a degree condition on a regular $n$-vertex graph $G$ which ensures the existence of a near optimal packing of any family $\mathcal H$ of bounded degree $n$-vertex $k$-chromatic separable graphs into $G$. In general, this degree…

Combinatorics · Mathematics 2018-11-12 Padraig Condon , Jaehoon Kim , Daniela Kühn , Deryk Osthus

In 1990 Erd\H{o}s, Faudree, Rousseau and Schelp proved that for $k\geq 2$, every graph with $n\geq k+1$ vertices and $(k-1)(n-k+2)+\binom{k-2}{2}+1$ edges contains a subgraph of minimum degree $k$ on at most $n-\sqrt{n}/\sqrt{6k^3}$…

Combinatorics · Mathematics 2017-03-02 Frank Mousset , Andreas Noever , Nemanja Škorić

A variant of the Erd\H{o}s-S\'os conjecture, posed by Havet, Reed, Stein and Wood, states that every graph with minimum degree at least $\lfloor 2k/3 \rfloor$ and maximum degree at least $k$ contains a copy of every tree with $k$ edges.…

Combinatorics · Mathematics 2025-12-19 Alexey Pokrovskiy , Leo Versteegen , Ella Williams

In this short note, we address two problems in extremal set theory regarding intersecting families. The first problem is a question posed by Kupavskii: is it true that given two disjoint cross-intersecting families $\mathcal{A}, \mathcal{B}…

Combinatorics · Mathematics 2018-05-01 Hao Huang

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

For any $k\ge 3$ and $\ell \in [k-1]$ such that $(k,\ell) \ne (3,1)$, we show that any sufficiently large $k$-graph $G$ must contain a Hamilton $\ell$-cycle provided that it has no isolated vertices and every set of $k-1$ vertices contained…

Combinatorics · Mathematics 2025-12-10 Shoham Letzter , Arjun Ranganathan

The classical Andr\'{a}sfai-Erd\H{o}s-S\'{o}s theorem considers the chromatic number of $K_{r + 1}$-free graphs with large minimum degree, and in the case $r = 2$ says that any $n$-vertex triangle-free graph with minimum degree greater than…

Combinatorics · Mathematics 2023-08-22 Freddie Illingworth

Recently, Alon and Frankl (JCTB, 2024) determined the maximum number of edges in $K_{\ell+1}$-free $n$-vertex graphs with bounded matching number. For integers $\ell\ge r \ge 2$, the family $\mathcal{K}_{\ell+1}^{r}$ consists of all…

Combinatorics · Mathematics 2025-11-27 Caihong Yang , Jiasheng Zeng , Xiao-Dong Zhang

In 1963, Corr\'adi and Hajnal settled a conjecture of Erd\H{o}s by proving that, for all $k \geq 1$, any graph $G$ with $|G| \geq 3k$ and minimum degree at least $2k$ contains $k$ vertex-disjoint cycles. In 2008, Finkel proved that for all…

Combinatorics · Mathematics 2015-11-16 Theodore Molla , Michael Santana , Elyse Yeager

Our main result improves bounds of Markstrom and Rucinski on the minimum d-degree which forces a perfect matching in a k-uniform hypergraph on n vertices. We also extend bounds of Bollobas, Daykin and Erdos by asymptotically determining the…

Combinatorics · Mathematics 2013-12-03 Daniela Kühn , Deryk Osthus , Timothy Townsend

We study optimal minimum degree conditions when an $n$-vertex graph $G$ contains an $r$-regular $r$-connected subgraph. We prove for $r$ fixed and $n$ large the condition to be $\delta(G) \ge \frac{n+r-2}{2}$ when $nr \equiv 0 \pmod 2$.…

Combinatorics · Mathematics 2021-08-18 Max Hahn-Klimroth , Olaf Parczyk , Yury Person

Let F be a family of r-uniform hypergraphs. The chromatic threshold of F is the infimum of all non-negative reals c such that the subfamily of F comprising hypergraphs H with minimum degree at least $c \binom{|V(H)|}{r-1}$ has bounded…

Combinatorics · Mathematics 2019-02-20 József Balogh , Jane Butterfield , Ping Hu , John Lenz , Dhruv Mubayi

We consider the Erd\H{o}s, Pach, Pollack and Tuza problem, asking for the maximum diameter of a graph with given order $n$, minimum degree $\delta$ and clique number at most $\omega$. We solve their problem asymptotically for the first hard…

Combinatorics · Mathematics 2025-02-13 Stijn Cambie , Jorik Jooken

The problem of determining extremal hypergraphs containing at most r isomorphic copies of some element of a given hypergraph family was first studied by Boros et al. in 2001. There are not many hypergraph families for which exact results…

Combinatorics · Mathematics 2007-12-18 Yeow Meng Chee , Alan C. H. Ling

This paper addresses the following question for a given graph $H$: what is the minimum number $f(H)$ such that every graph with average degree at least $f(H)$ contains $H$ as a minor? Due to connections with Hadwiger's Conjecture, this…

Combinatorics · Mathematics 2019-02-20 Bruce Reed , David R. Wood

For a positive integer $k$, a graph is $k$-knitted if for each $k$-subset $S$ of vertices, and every partition of $S$ into disjoint parts $S_1, \ldots, S_t$ for some $t\ge 1$, one can find disjoint connected subgraphs $C_1, \ldots, C_t$…

Combinatorics · Mathematics 2019-06-11 Runrun Liu , Martin Rolek , Gexin Yu
‹ Prev 1 4 5 6 7 8 10 Next ›