English
Related papers

Related papers: Sharp Thresholds for Factors in Random Graphs

200 papers

We continue the study of the properties of graphs in which the ball of radius $r$ around each vertex induces a graph isomorphic to the ball of radius $r$ in some fixed vertex-transitive graph $F$, for various choices of $F$ and $r$. This is…

Combinatorics · Mathematics 2020-11-25 Itai Benjamini , David Ellis

Given two $k$-graphs $F$ and $H$, a perfect $F$-tiling (also called an $F$-factor) in $H$ is a set of vertex disjoint copies of $F$ that together cover the vertex set of $H$. Let $t_{k-1}(n, F)$ be the smallest integer $t$ such that every…

Combinatorics · Mathematics 2018-05-16 Xinmin Hou , Boyuan Liu , Yue Ma

We call a set $\mathcal S$ of graphs an "even subdivison-factor" of a cubic graph $G$ if $G$ contains a spanning subgraph $H$ such that every component of $H$ has an even number of vertices and is a subdivision of an element of $\mathcal…

Combinatorics · Mathematics 2012-11-12 Arthur Hoffmann-Ostenhof

Given a graph $H$, a balanced subdivision of $H$ is a graph obtained from $H$ by subdividing every edge the same number of times. In 1984, Thomassen conjectured that for each integer $k\ge 1$, high average degree is sufficient to guarantee…

Combinatorics · Mathematics 2023-02-21 Bingyu Luan , Yantao Tang , Guanghui Wang , Donglei Yang

We present a new sufficient condition on stability number and toughness of the graph to have an f-factor.

Discrete Mathematics · Computer Science 2010-11-03 Kouider Mekkia

A graph $G$ of order $n$ is said to be $k$-factor-critical for integers $1\leq k< n$, if the removal of any $k$ vertices results in a graph with a perfect matching. A $k$-factor-critical graph is minimal if for every edge, the deletion of…

Combinatorics · Mathematics 2024-12-31 Jing Guo , Qiuli Li , Fuliang Lu , Heping Zhang

We locate the critical threshold $p_c$ at which it becomes likely that the complete graph $K_n$ can be obtained from the Erd\H{o}s-R\'enyi graph ${\cal G}_{n,p}$ by iteratively completing copies of $K_4$ minus an edge. This refines work of…

Probability · Mathematics 2025-11-18 Brett Kolesnik

The codegree threshold $\mathrm{ex}_2(n, F)$ of a $3$-graph $F$ is the minimum $d=d(n)$ such that every $3$-graph on $n$ vertices in which every pair of vertices is contained in at least $d+1$ edges contains a copy of $F$ as a subgraph. We…

Combinatorics · Mathematics 2022-12-22 Victor Falgas-Ravry , Oleg Pikhurko , Emil R. Vaughan , Jan Volec

Given a collection of graphs $\mathbf{G}=(G_1, \ldots, G_m)$ with the same vertex set, an $m$-edge graph $H\subset \cup_{i\in [m]}G_i$ is a transversal if there is a bijection $\phi:E(H)\to [m]$ such that $e\in E(G_{\phi(e)})$ for each…

Combinatorics · Mathematics 2022-05-04 Richard Montgomery , Alp Müyesser , Yanitsa Pehova

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

In this work, we develop a unified framework for establishing sharp threshold results for various Ramsey properties. To achieve this, we view such properties as non-colourability of auxiliary hypergraphs. Our main technical result gives…

Combinatorics · Mathematics 2026-03-04 Ehud Friedgut , Eden Kuperwasser , Wojciech Samotij , Mathias Schacht

Finding a d-regular spanning subgraph (or d-factor) of a graph is easy by Tutte's reduction to the matching problem. By the same reduction, it is easy to find a minimal or maximal d-factor of a graph. However, if we require that the…

Data Structures and Algorithms · Computer Science 2013-10-10 Kamiel Cornelissen , Ruben Hoeksma , Bodo Manthey , N. S. Narayanaswamy , C. S. Rahul

Let $a$, $b$, and $n$ be three integers such that $1\leq a \leq b < n$, $a \equiv b$ (mod $2$), and $na$ is even. A parity $[a,b]$-factor of $G$ is a spanning subgraph $H$ such that for each vertex $v \in V(G)$, $a \leq d_H(v) \leq b$ and…

Combinatorics · Mathematics 2026-02-03 Ruifang Liu , Ting Xu , Suil O

A spanning subgraph $F$ of a graph $G$ is defined as an even factor of $G$, if the degree $d_F(v)=2k, k\in\mathbb{N}^+$ for every vertex $v\in V(G)$. This note establishes a sufficient condition to ensure that a connected graph $G$ of even…

Combinatorics · Mathematics 2025-12-02 Lu Li , Hechao Liu , Hongbo Hua , Zenan Du

Given a family of graphs $\mathcal{F}$ and an integer $r$, we say that a graph is $r$-Ramsey for $\mathcal{F}$ if any $r$-colouring of its edges admits a monochromatic copy of a graph from $\mathcal{F}$. The threshold for the classic Ramsey…

Combinatorics · Mathematics 2024-11-27 Eden Kuperwasser , Wojciech Samotij

Let $F$ be a strictly $1$-balanced $k$-graph on $s$ vertices with $t$ edges and $\delta_{F,d}^T$ be the infimum of $\delta>0$ such that for every $\alpha>0$ and sufficiently large $n\in \mathbb{N}$, every $k$-graph system $\mathbf…

Combinatorics · Mathematics 2025-07-18 Jie Han , Jie Hu , Shunan Wei , Donglei Yang

Let $k$, $m$ and $r$ be three integers such that $2\leq k\leq m\leq r$. Let $G$ be a $2r$-regular, $2m$-edge-connected graph of odd order. We obtain some sufficient conditions, which guarantee $G-v$ contains a $k$-factor for all $v\in…

Combinatorics · Mathematics 2010-07-27 Hongliang Lu , Bing Bai , Wei Wang

Given a sequence $\mathbf{k} := (k_1,\ldots,k_s)$ of natural numbers and a graph $G$, let $F(G;\mathbf{k})$ denote the number of colourings of the edges of $G$ with colours $1,\dots,s$ such that, for every $c \in \{1,\dots,s\}$, the edges…

Combinatorics · Mathematics 2023-05-09 Oleg Pikhurko , Katherine Staden

We derive a simple formula characterizing the distribution of the size of the connected component of a fixed vertex in the Erd\H{o}s-R\'enyi random graph which allows us to give elementary proofs of some results of Federico, van der…

Probability · Mathematics 2018-04-27 Balazs Rath

Inspired by previous work of Diaz, Petit, Serna, and Trevisan (Approximating layout problems on random graphs Discrete Mathematics, 235, 2001, 245--253), we show that several well-known graph layout problems are approximable to within a…

Combinatorics · Mathematics 2017-10-31 Kevin K. H. Cheung , Patrick D. Girardet