English
Related papers

Related papers: Star Saturation Number of Random Graphs

200 papers

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

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

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

The saturation number of a graph $G$ is the cardinality of any smallest maximal matching of $G$, and it is denoted by $s(G)$. Fullerene graphs are cubic planar graphs with exactly twelve 5-faces; all the other faces are hexagons. They are…

Combinatorics · Mathematics 2014-05-12 Vesna Andova , František Kardoš , Riste Škrekovski

A graph $G$ is called {\em$F$-saturated} if $G$ does not contain $F$ as a subgraph but adding any missing edge to $G$ creates a copy of $F$. In this paper, we consider the spectral saturation problem for the linear forest $tP_4$, proving…

Combinatorics · Mathematics 2026-02-11 Junxue Zhang , Liwen Zhang

We investigate two notions of saturation for partial planar embeddings of maximal planar graphs. Let $G = (V, E) $ be a vertex-labeled maximal planar graph on $ n $ vertices, which by definition has $3n - 6$ edges. We say that a labeled…

Combinatorics · Mathematics 2024-12-10 Alexander Clifton , Dániel G. Simon

A hypergraph $H=(V(H), E(H))$ is a Berge copy of a graph $F$, if $V(F)\subset V(H)$ and there is a bijection $f:E(F)\rightarrow E(H)$ such that for any $e\in E(F)$ we have $e\subset f(e)$. A hypergraph is Berge-$F$-free if it does not…

Combinatorics · Mathematics 2021-03-16 Dániel Gerbner , Balázs Patkós , Zsolt Tuza , Máté Vizer

A graph $G$ is called $C_k$-saturated if $G$ is $C_k$-free but $G+e$ not for any $e\in E(\overline{G})$. The saturation number of $C_k$, denoted $sat(n,C_k)$, is the minimum number of edges in a $C_k$-saturated graph on $n$ vertices.…

Combinatorics · Mathematics 2023-11-08 Yongxin Lan , Yongtang Shi , Yiqiao Wang , Junxue Zhang

For a graph G, a hypergraph H is called Berge-G if there is a hypergraph H', isomorphic to H, containing all vertices of G, so that e is contained in f(e) for each edge e of G, where f is a bijection between E(G) and E(H'). The set of all…

Combinatorics · Mathematics 2018-10-31 Maria Axenovich , Christian Winter

We investigate the extremal properties of saturated partial plane embeddings of maximal planar graphs. For a planar graph $G$, the plane-saturation number $\mathrm{sat}_{\mathcal{P}}(G)$ denotes the minimum number of edges in a plane…

Combinatorics · Mathematics 2025-02-11 János Barát , Zoltán L. Blázsik , Balázs Keszegh , Zeyu Zheng

Given graphs $H_1, \dots, H_t$, a graph $G$ is $(H_1, \dots, H_t)$-Ramsey-minimal if every $t$-coloring of the edges of $G$ contains a monochromatic $H_i$ in color $i$ for some $i\in\{1, \dots, t\}$, but any proper subgraph of $G $ does not…

Combinatorics · Mathematics 2018-08-14 Martin Rolek , Zi-Xia Song

Given a graph $H$, we say that an edge-coloured graph $G$ is $H$-rainbow saturated if it does not contain a rainbow copy of $H$, but the addition of any non-edge in any colour creates a rainbow copy of $H$. The rainbow saturation number…

Combinatorics · Mathematics 2024-04-17 Natalie Behague , Tom Johnston , Shoham Letzter , Natasha Morrison , Shannon Ogden

For a fixed graph $F$ and an integer $t$, the \dfn{rainbow saturation number} of $F$, denoted by $sat_t(n,\mathfrak{R}(F))$, is defined as the minimum number of edges in a $t$-edge-colored graph on $n$ vertices which does not contain a…

Combinatorics · Mathematics 2020-01-20 Shujuan Cao , Yuede Ma , Zhenyu Taoqiu

Given a graph $H$, we say that a graph $G$ is properly rainbow $H$-saturated if: (1) There is a proper edge colouring of $G$ containing no rainbow copy of $H$; (2) For every $e \notin E(G)$, every proper edge colouring of $G+e$ contains a…

Combinatorics · Mathematics 2024-10-15 Andrew Lane , Natasha Morrison

A graph $H^{\prime}$ is $(H, G)$-saturated if it is $G$-free and the addition of any edge of $H$ not in $H^{\prime}$ creates a copy of $G$. The saturation number $sat(H, G)$ is the minimum number of edges in a $(H, G)$-saturated graph. We…

Combinatorics · Mathematics 2014-11-12 Kavish Gandhi , Chiheon Kim

For a fixed graph $H$, a graph $G$ is called $H$-saturated if $G$ does not contain $H$ as a (not necessarily induced) subgraph, but $G+e$ contains a copy of $H$ for any $e\in E(\overline{G})$. The saturation number of $H$, denoted by ${\rm…

Combinatorics · Mathematics 2025-03-17 Ning Song , Jinze Hu , Shengjin Ji , Qing Cui

Let $G=(V,E)$ be a simple connected graph. A matching $M$ in a graph $G$ is a collection of edges of $G$ such that no two edges from $M$ share a vertex. A matching $M$ is maximal if it cannot be extended to a larger matching in $G$. The…

Combinatorics · Mathematics 2017-12-12 Saeid Alikhani , Neda Soltani

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

An edge-coloring of a graph $H$ is a function $\mathcal{C}: E(H) \rightarrow \mathbb{N}$. We say that $H$ is rainbow if all edges of $H$ have different colors. Given a graph $F$, an edge-colored graph $G$ is $F$-rainbow saturated if $G$…

Combinatorics · Mathematics 2025-01-14 Yiduo Xu , Zhen He , Mei Lu

A graph $G$ is called $H$-saturated if $G$ contains no copy of $H$, but $G+e$ contains a copy of $H$ for any edge $e\in E(\overline{G})$. The saturation number of $H$ is the minimum number of edges in an $H$-saturated graph of order $n$,…

Combinatorics · Mathematics 2025-11-26 Xiaoxue Zhang , Lihua You , Xinghui Zhao