English
Related papers

Related papers: Rational values of the weak saturation limit

200 papers

For an edge-ordered graph $G$, we say that an $n$-vertex edge-ordered graph $H$ is $G$-saturated if it is $G$-free and adding any new edge with any new label to $H$ introduces a copy of $G$. The saturation function describes the minimum…

Combinatorics · Mathematics 2024-08-02 Vladimir Bošković , Balázs Keszegh

We introduce weak oddness $\omega_{\textrm w}$, a new measure of uncolourability of cubic graphs, defined as the least number of odd components in an even factor. For every bridgeless cubic graph $G$, $\rho(G)\le\omega_{\textrm…

Discrete Mathematics · Computer Science 2016-02-10 Robert Lukoťka , Ján Mazák

A graph $G$ is $H$-saturated if it contains no copy of $H$ as a subgraph but the addition of any new edge to $G$ creates a copy of $H$. In this paper we are interested in the function sat$_{t}(n,p)$, defined to be the minimum number of…

Combinatorics · Mathematics 2016-12-16 A. Nicholas Day

For a given graph $F$, the $F$-saturation number of a graph $G$, denoted by $ {sat}(G, F)$, is the minimum number of edges in an edge-maximal $F$-free subgraph of $G$. In 2017, Kor\'andi and Sudakov determined $ {sat}({G}(n, p), K_r)$…

Combinatorics · Mathematics 2023-04-18 Meysam Miralaei , Ali Mohammadian , Behruz Tayfeh-Rezaie , Maksim Zhukovskii

Graph-bootstrap percolation, also known as weak saturation, was introduced by Bollob\'as in 1968. In this process, we start with initial "infected" set of edges $E_0$, and we infect new edges according to a predetermined rule. Given a graph…

Combinatorics · Mathematics 2019-07-11 József Balogh , Gal Kronenberg , Alexey Pokrovskiy , Tibor Szabó

We say that an edge-coloring of a graph $G$ is proper if every pair of incident edges receive distinct colors, and is rainbow if no two edges of $G$ receive the same color. Furthermore, given a fixed graph $F$, we say that $G$ is rainbow…

Combinatorics · Mathematics 2026-02-19 Anastasia Halfpap , Bernard Lidický , Tomáš Masařík

We prove that determining the weak saturation number of a host graph $F$ with respect to a pattern graph $H$ is already a computationally hard problem when $H$ is the triangle. As our main tool we establish a connection between weak…

Combinatorics · Mathematics 2025-10-22 Martin Tancer , Mykhaylo Tyomkyn

We study the weak $K_s$-saturation number of the Erd\H{o}s--R\'{e}nyi random graph $\mathbbmsl{G}(n, p)$, denoted by $\mathrm{wsat}(\mathbbmsl{G}(n, p), K_s)$, where $K_s$ is the complete graph on $s$ vertices. Kor\'{a}ndi and Sudakov in…

Combinatorics · Mathematics 2021-11-16 M. Bidgoli , A. Mohammadian , B. Tayfeh-Rezaie , M. Zhukovskii

The saturation number $\operatorname{sat}(n, H)$ of a graph $H$ and positive integer $n$ is the minimum size of a graph of order $n$ which does not contain a subgraph isomorphic to $H$ but to which the addition of any edge creates such a…

Combinatorics · Mathematics 2025-07-29 Calum Buchanan , Puck Rombach

Let $F$ and $H$ be $k$-uniform hypergraphs. We say $H$ is $F$-saturated if $H$ does not contain a subgraph isomorphic to $F$, but $H+e$ does for any hyperedge $e\not\in E(H)$. The saturation number of $F$, denoted $\mathrm{sat}_k(n,F)$, is…

Combinatorics · Mathematics 2022-02-16 Sean English , Alexandr Kostochka , Dara Zirlin

A graph $G$ is $H$-saturated if it contains no $H$ as a subgraph, but does contain $H$ after the addition of any edge in the complement of $G$. The saturation number, $sat (n, H)$, is the minimum number of edges of a graph in the set of all…

Combinatorics · Mathematics 2021-10-19 Jingru Yan

For a family $\mathcal{F}$ of graphs, $sat(n,\mathcal{F})$ is the minimum number of edges in a graph $G$ on $n$ vertices which does not contain any of the graphs in $\mathcal{F}$ but such that adding any new edge to $G$ creates a graph in…

Combinatorics · Mathematics 2024-01-22 Asier Calbet , Andrea Freschi

This paper considers two important questions in the well-studied theory of graphs that are $F$-saturated. A graph $G$ is called $F$-saturated if $G$ does not contain a subgraph isomorphic to $F$, but the addition of any edge creates a copy…

Combinatorics · Mathematics 2020-07-17 Debsoumya Chakraborti , Po-Shen Loh

For a given graph $F$, the $F$-saturation number of a graph $G$ is the minimum number of edges in an edge-maximal $F$-free subgraph of $G$. Recently, the $F$-saturation number of the Erd\H{o}s$\text{\bf--}$R\'enyi random graph…

Combinatorics · Mathematics 2017-09-26 A. Mohammadian , B. Tayfeh-Rezaie

The forbidden subgraph problem is among the oldest in extremal combinatorics -- how many edges can an $n$-vertex $F$-free graph have? The answer to this question is the well-studied extremal number of $F$. Observing that every extremal…

Combinatorics · Mathematics 2025-02-26 Neal Bushaw , Sean English , Emily Heath , Daniel P. Johnston , Puck Rombach

Given graphs $H$ and $F$, a subgraph $G\subseteq H$ is an $F$-saturated subgraph of $H$ if $F\nsubseteq G$, but $F\subseteq G+e$ for all $e\in E(H)\setminus E(G)$. The saturation number of $F$ in $H$, denoted $\text{sat}(H,F)$, is the…

Combinatorics · Mathematics 2014-08-27 Eric Sullivan , Paul S. Wenger

Given a family ${\mathcal F}$ and a host graph $H$, a graph $G\subseteq H$ is ${\mathcal F}$-saturated relative to $H$ if no subgraph of $G$ lies in ${\mathcal F}$ but adding any edge from $E(H)-E(G)$ to $G$ creates such a subgraph. In the…

Combinatorics · Mathematics 2014-06-12 James M. Carraher , William B. Kinnersley , Benjamin Reiniger , Douglas B. West

A graph $H$ is $K_s$-saturated if it is a maximal $K_s$-free graph, i.e., $H$ contains no clique on $s$ vertices, but the addition of any missing edge creates one. The minimum number of edges in a $K_s$-saturated graph was determined over…

Combinatorics · Mathematics 2016-04-14 Dániel Korándi , Benny Sudakov

A graph $G$ is $F$-saturated if it does not contain any copy of $F$, but the addition of any missing edge in $G$ creates at least one copy of $F$. Inspired by work of Alon and Shikhelman regarding a similar question for $F$-free graphs,…

Combinatorics · Mathematics 2021-08-18 Jamie Radcliffe , Adam Volk

Let $\mathbb{N}_0$ be the set of all non-negative integers, let $X\subset \mathbb{N}_0$ and $\mathcal{P}(X)$ be the the power set of $X$. An integer additive set-labeling (IASL) of a graph $G$ is an injective function $f:V(G)\to…

General Mathematics · Mathematics 2015-03-27 N. K. Sudev , K. P. Chithra , K. A. Germina