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Related papers: On well-covered Cartesian products

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We say that a graph $G$ has an {\em odd $K_4$-subdivision} if some subgraph of $G$ is isomorphic to a $K_4$-subdivision and whose faces are all odd holes of $G$. For a number $\ell\geq 2$, let $\mathcal{G}_{\ell}$ denote the family of…

Combinatorics · Mathematics 2024-01-03 Rong Chen , Yidong Zhou

A "clique minor" in a graph G can be thought of as a set of connected subgraphs in G that are pairwise disjoint and pairwise adjacent. The "Hadwiger number" h(G) is the maximum cardinality of a clique minor in G. This paper studies clique…

Combinatorics · Mathematics 2011-10-05 David R. Wood

A graph is well-covered if all its maximal independent sets have the same cardinality. This well studied concept was introduced by Plummer in 1970 and naturally generalizes to the weighted case. Given a graph $G$, a real-valued vertex…

Combinatorics · Mathematics 2023-10-20 Martin Milanič , Nevena Pivač

It was recently proved that every planar graph is a subgraph of the strong product of a path and a graph with bounded treewidth. This paper surveys generalisations of this result for graphs on surfaces, minor-closed classes, various…

Combinatorics · Mathematics 2021-02-18 Zdeněk Dvořák , Tony Huynh , Gwenaël Joret , Chun-Hung Liu , David R. Wood

This paper is concerned with the recognition of approximate graph products with respect to the Cartesian product. Most graphs are prime, although they can have a rich product-like structure. The proposed algorithms are based on a local…

Discrete Mathematics · Computer Science 2014-07-14 Marc Hellmuth , Wilfried Imrich , Tomas Kupka

We determine the thickness of the Cartesian product $K_{6p+4} \square P_2$ for $p \ge 0$ and of the Cartesian product $K_8 \square P_m$ for $m \ge 1$, where $K_n$ and $P_m$ denote the complete graph on $n$ vertices and the path on $m$…

Combinatorics · Mathematics 2026-03-31 Kenta Noguchi

The double graph of a graph $G$ is defined as $\mathcal{D}[G]$ = $G \times T_2$, where \(T_2\) is the total graph with 2 vertices and $\times$ stands for the Kronecker product of graphs. In this paper, sufficient conditions for double…

Combinatorics · Mathematics 2015-04-24 Zhayida Simayijiang , Elkin Vumar

For a graph $G$, let $im(G)$ denote the maximum integer $t$ such that $G$ contains $K_t$ as an immersion. A recent paper of Collins, Heenehan, and McDonald (2023) studied the behaviour of this parameter under graph products, asking how…

Combinatorics · Mathematics 2025-11-24 Henry Echeverría , Andrea Jiménez , Suchismita Mishra , Daniel A. Quiroz , Mauricio Yépez

A graph $G$ is called matching covered if all of its edges are contained in some perfect matching of $G$. Furthermore, a cycle $C \subseteq G$ is called conformal if $G - V(C)$ has a perfect matching and $G$ itself is called cycle-conformal…

Combinatorics · Mathematics 2026-02-10 Maximilian Gorsky , Clemens Kuske

The thickness of a graph $G$ is the minimum number of planar subgraphs whose union is $G$. In this paper, we present sharp lower and upper bounds for the thickness of the Kronecker product $G\times H$ of two graphs $G$ and $H$. We also give…

Combinatorics · Mathematics 2019-01-25 Xia Guo , Yan Yang

In this paper, we show that if $G$ is $3$-connected, then the Cartesian product of graphs $G \square H$ embeds on the torus if and only if $G$ is outer-cylindrical and $H$ is a path on two vertices, $P_2$. As a by-product of our work, we…

Combinatorics · Mathematics 2026-04-22 Elizabeth Badgett , Christian Millichap , Kenta Noguchi

An identifying code in a graph $G$ is a dominating set $C$ such that the closed neighborhood of each vertex in $G$ has a distinct intersection with $C$. In 2008, Gravier et al. determined the minimum cardinality of an identifying code of…

Combinatorics · Mathematics 2014-12-09 Yingnan Zhang , Min Feng , Kaishun Wang

Let $k \geq 2$ be an integer. We say that a graph $G$ is $(K_2 \cup kK_1)$-free if it does not contain $K_2 \cup kK_1$ as an induced subgraph. Recently, Shi and Shan conjectured that every $1$-tough and $2k$-connected $(K_2 \cup kK_1)$-free…

Combinatorics · Mathematics 2023-02-22 Katsuhiro Ota , Masahiro Sanka

If $G$ is a graph and $X\subseteq V(G)$, then $X$ is a total mutual-visibility set if every pair of vertices $x$ and $y$ of $G$ admits a shortest $x,y$-path $P$ with $V(P) \cap X \subseteq \{x,y\}$. The cardinality of a largest total…

Combinatorics · Mathematics 2022-12-15 Jing Tian , Sandi Klavžar

An $(r, \ell)$-partition of a graph $G$ is a partition of its vertex set into $r$ independent sets and $\ell$ cliques. A graph is $(r, \ell)$ if it admits an $(r, \ell)$-partition. A graph is well-covered if every maximal independent set is…

Data Structures and Algorithms · Computer Science 2018-06-07 Sancrey R. Alves , Konrad K. Dabrowski , Luerbio Faria , Sulamita Klein , Ignasi Sau , Uéverton S. Souza

In this paper, we introduce the concept of $k$-integral graphs. A graph $\Gamma$ is called $k$-integral if the extension degree of the splitting field of the characteristic polynomial of $\Gamma$ over rational field $\mathbb Q$ is equal to…

Combinatorics · Mathematics 2025-08-06 Alireza Abdollahi , Majid Arezoomand , Tao Feng , Shixin Wang

Gravier et al. investigated the identifying codes of Cartesian product of two graphs. In this paper we consider the identifying codes of lexicographic product G[H] of a connected graph G and an arbitrary graph H, and obtain the minimum…

Combinatorics · Mathematics 2013-12-20 Min Feng , Min Xu , Kaishun Wang

A family of independent $r$-sets of a graph $G$ is an $r$-star if every set in the family contains some fixed vertex $v$. A graph is $r$-EKR if the maximum size of an intersecting family of independent $r$-sets is the size of an $r$-star.…

Combinatorics · Mathematics 2023-04-19 Jessica De Silva , Adam B. Dionne , Aidan Dunkelberg , Pamela E. Harris

A graph $G$ is well-covered if all maximal independent sets are of the same cardinality. Let $w:V(G) \longrightarrow\mathbb{R}$ be a weight function. Then $G$ is $w$-well-covered if all maximal independent sets are of the same weight. An…

Combinatorics · Mathematics 2024-03-25 Vadim E. Levit , David Tankus

The k-fold Cartesian product of a graph G is defined as a graph on k-tuples of vertices, where two tuples are connected if they form an edge in one of the positions and are equal in the rest. Starting with G as a single edge gives G^k as a…

Discrete Mathematics · Computer Science 2013-09-25 Sushant Sachdeva , Madhur Tulsiani