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Related papers: Weak saturation in graphs: a combinatorial approac…

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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 $G$ and $H$, $G$ is $H$-saturated if $H$ is not a subgraph of $G$, but for all $e \notin E(G)$, $H$ appears as a subgraph of $G + e$. While for every $n \ge |V(H)|$, there exists an $n$-vertex graph that is $H$-saturated, the…

Combinatorics · Mathematics 2015-03-10 Sarah Behrens , Catherine Erbes , Michael Santana , Derrek Yager , Elyse Yeager

A graph $H$ is said to be $F$-saturated relative to $G$, if $H$ does not contain any copy of $F$, but the addition of any edge $e$ in $E(G)\backslash E(H)$ would create a copy of $F$. The minimum size of an $F$-saturated graph relative to…

Combinatorics · Mathematics 2024-11-12 Yiduo Xu , Zhen He , Mei Lu

For given graphs $F$ and $G$, the minimum number of edges in an inclusion-maximal $F$-free subgraph of $G$ is called the $F$-saturation number and denoted $\mathrm{sat}(G, F)$. For the star $F=K_{1,r}$, the asymptotics of…

Combinatorics · Mathematics 2022-12-13 Sergej Demyanov , Maksim Zhukovskii

For a graph $F$, we say that another graph $G$ is $F$-saturated, if $G$ is $F$-free and adding any edge to $G$ would create a copy of $F$. We study for a given graph $F$ and integer $n$ whether there exists a regular $n$-vertex…

Combinatorics · Mathematics 2020-12-22 Dániel Gerbner , Balázs Patkós , Zsolt Tuza , Máté Vizer

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

As introduced by Bollob\'as, a graph $G$ is weakly $H$-saturated if the complete graph $K_n$ is obtained by iteratively completing copies of $H$ minus an edge. For all graphs $H$, we obtain an asymptotic lower bound for the critical…

Probability · Mathematics 2025-11-18 Zsolt Bartha , Brett Kolesnik

Let $H$ be a fixed graph. A graph $G$ is called {\it $H$-saturated} if $H$ is not a subgraph of $G$ but the addition of any missing edge to $G$ results in an $H$-subgraph. The {\it saturation number} of $H$, denoted $sat(n,H)$, is the…

Combinatorics · Mathematics 2024-04-19 Wen-Han Zhu , Rong-Xia Hao , Zhen He

A graph is $F$-saturated if it is $F$-free but the addition of any edge creates a copy of $F$. In this paper we study the quantity $\mathrm{sat}(n, H, F)$ which denotes the minimum number of copies of $H$ that an $F$-saturated graph on $n$…

Combinatorics · Mathematics 2018-10-16 Jürgen Kritschgau , Abhishek Methuku , Michael Tait , Craig Timmons

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

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

Let $H$ be a fixed graph, a graph G is $H$-saturated if it has no copy of $H$ in $G$, but the addition of any edge in $E(\overline G)$ to $G$ results in an $H$-subgraph. The saturation number sat$(n,H)$ is the minimum number of edges in an…

Combinatorics · Mathematics 2024-08-14 Yu Zhang , Rong-Xia Hao , Zhen He , Wen-Han Zhu

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

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

Graph $G$ is $F$-saturated if $G$ contains no copy of graph $F$ but any edge added to $G$ produces at least one copy of $F$. One common variant of saturation is to remove the former restriction: $G$ is $F$-semi-saturated if any edge added…

Combinatorics · Mathematics 2019-05-22 Danny Rorabaugh

A numbering $f$ of a graph $G$ of order $n$ is a labeling that assigns distinct elements of the set $\left\{ 1,2,\ldots ,n\right\} $ to the vertices of $G$. The strength $\textrm{str}_{f}\left( G\right)$ of a numbering $f:V\left( G\right)…

Combinatorics · Mathematics 2023-04-04 Yukio Takahashi , Rikio Ichishima , Francesc A. Muntaner-Batle

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 $\beta>0$. Motivated by jumbled graphs defined by Thomason, the celebrated expander mixing lemma and Haemers's vertex separation inequality, we define that a graph $G$ with $n$ vertices is a weakly $(n,\beta)$-graph if $\frac{|X|…

Combinatorics · Mathematics 2022-05-31 Xiaofeng Gu , Muhuo Liu

Let $Q_d$ denote the hypercube of dimension $d$. Given $d\geq m$, a spanning subgraph $G$ of $Q_d$ is said to be $(Q_d,Q_m)$-saturated if it does not contain $Q_m$ as a subgraph but adding any edge of $E(Q_d)\setminus E(G)$ creates a copy…

Combinatorics · Mathematics 2016-04-06 Natasha Morrison , Jonathan A. Noel , Alex Scott

The saturation number $\text{sat}_r(n,\mathcal{F})$ is the minimum number of hyperedges in an $r$-uniform $\mathcal{F}$-saturated hypergraph on $n$ vertices. We determine this parameter for $3$-uniform Berge-$K_4$ hypergraphs, proving that…

Combinatorics · Mathematics 2026-01-27 Yihan Chen , Jialin He , Tianying Xie