English
Related papers

Related papers: Thickness and Outerthickness for Embedded Graphs

200 papers

The bondage number b(G) of a graph G is the smallest number of edges of G whose removal from G results in a graph having the domination number larger than that of G. We show that, for a graph G having the maximum vertex degree $\Delta(G)$…

Combinatorics · Mathematics 2016-04-25 Andrei Gagarin , Vadim Zverovich

In this paper, extending a result of Brooks et.al. [arXiv:2403.04110], we show that if an outerplanar graph $G$ with minimum degree at least $2$ has positive Lin-Lu-Yau curvature on every vertex pair, then $G$ has at most $10$ vertices, and…

Combinatorics · Mathematics 2024-09-23 Xiaonan Liu , Linyuan Lu , Zhiyu Wang

A graph is 2-degenerate if every subgraph contains a vertex of degree at most 2. We show that every 2-degenerate graph can be drawn with straight lines such that the drawing decomposes into 4 plane forests. Therefore, the geometric…

Combinatorics · Mathematics 2023-03-01 Rahul Jain , Marco Ricci , Jonathan Rollin , André Schulz

The $g$-girth-thickness $\theta(g,G)$ of a graph $G$ is the minimum number of planar subgraphs of girth at least $g$ whose union is $G$. In this paper, we determine the $6$-girth-thickness $\theta(6,K_n)$ of the complete graph $K_n$ in…

Twin-width is a width parameter introduced by Bonnet, Kim, Thomass\'e and Watrigant [FOCS'20, JACM'22], which has many structural and algorithmic applications. We prove that the twin-width of every graph embeddable in a surface of Euler…

Combinatorics · Mathematics 2024-02-12 Daniel Kráľ , Kristýna Pekárková , Kenny Štorgel

We define the geometric thickness of a graph to be the smallest number of layers such that we can draw the graph in the plane with straight-line edges and assign each edge to a layer so that no two edges on the same layer cross. The…

Combinatorics · Mathematics 2007-05-23 Michael B. Dillencourt , David Eppstein , Daniel S. Hirschberg

A $(2,1)$-total labeling of a graph $G$ is an assignment $f$ from the vertex set $V(G)$ and the edge set $E(G)$ to the set $\{0,1,...,k\}$ of nonnegative integers such that $|f(x)-f(y)|\ge 2$ if $x$ is a vertex and $y$ is an edge incident…

Discrete Mathematics · Computer Science 2009-11-25 Toru Hasunuma , Toshimasa Ishii , Hirotaka Ono , Yushi Uno

The bend-number b(G) of a graph G is the minimum k such that G may be represented as the edge intersection graph of a set of grid paths with at most k bends. We confirm a conjecture of Biedl and Stern showing that the maximum bend-number of…

Combinatorics · Mathematics 2011-12-16 Daniel Heldt , Kolja Knauer , Torsten Ueckerdt

In this article we present theoretical and computational results on the existence of polyhedral embeddings of graphs. The emphasis is on cubic graphs. We also describe an efficient algorithm to compute all polyhedral embeddings of a given…

Combinatorics · Mathematics 2023-06-22 Gunnar Brinkmann , Thomas Tucker , Nico Van Cleemput

A graph is $2$-planar if it has local crossing number two, that is, it can be drawn in the plane such that every edge has at most two crossings. A graph is maximal $2$-planar if no edge can be added such that the resulting graph remains…

Combinatorics · Mathematics 2023-03-16 Michael Hoffmann , Meghana M. Reddy

In a book embedding of a graph G, the vertices of G are placed in order along a straight-line called spine of the book, and the edges of G are drawn on a set of half-planes, called the pages of the book, such that two edges drawn on a page…

Computational Geometry · Computer Science 2015-10-21 Md. Jawaherul Alam , Franz J. Brandenburg , Stephen G. Kobourov

A graph is 1-planar if it can be drawn in the plane such that each edge is crossed at most once. A graph, together with a 1-planar drawing is called 1-plane. Brandenburg et al. showed that there are maximal 1-planar graphs with only…

Combinatorics · Mathematics 2015-09-21 János Barát , Géza Tóth

A key concept for many graph layout algorithms is planarity, a graph property that allows to draw vertices and edges crossing-free in the plane. Important is the generalization to $k$-planar graphs, which can be drawn in the plane with at…

Discrete Mathematics · Computer Science 2026-05-18 Aaron Büngener , Jakob Franz , Michael Kaufmann , Maximilian Pfister

It is well known that the spectral radius of a tree whose maximum degree is $D$ cannot exceed $2\sqrt{D-1}$. In this paper we derive similar bounds for arbitrary planar graphs and for graphs of bounded genus. It is proved that a the…

Combinatorics · Mathematics 2011-01-14 Zdenek Dvorak , Bojan Mohar

The skewness of a graph G is the minimum number of edges in G whose removal results in a planar graph. By appropriately introducing a weight to each edge of a graph, we determine, among other thing, the skewness of the generalized Petersen…

Combinatorics · Mathematics 2017-09-20 Gek L. Chia , Chan L. Lee , Yan Hao Ling

The $g$-girth-thickness $\theta(g,G)$ of a graph $G$ is the smallest number of planar subgraphs of girth at least $g$ whose union is $G$. In this paper, we calculate the $4$-girth-thickness $\theta(4,G)$ of the complete $m$-partite graph…

Combinatorics · Mathematics 2019-10-29 Christian Rubio-Montiel

The $n$-$book ~embedding$ of a graph $G$ is an embedding of the graph $G$ in an $n$-book with the vertices of $G$ on the spine and each edge to the pages without crossing each other. If the degree of vertices of $G$ at most one in each…

Combinatorics · Mathematics 2022-08-15 Zeling Shao , Yanqing Liu , Zhiguo Li

In this paper, we study the metric dimension problem in maximal outerplanar graphs. Concretely, if $\beta (G)$ is the metric dimension of a maximal outerplanar graph $G$ of order $n$, we prove that $2\le \beta (G) \le \lceil…

A graph is outerplanar if it has a planar drawing for which all vertices belong to the outer face of the drawing. Let $H$ be a graph. The outerplanar Tur\'an number of $H$, denoted by $ex_\mathcal{OP}(n,H)$, is the maximum number of edges…

Combinatorics · Mathematics 2023-10-03 Ervin Győri , Guilherme Zeus Dantas e Moura , Runtian Zhou

In this paper, we show that all simple outerplanar graphs $G$ with minimum degree at least $2$ and positive Lin-Lu-Yau Ricci curvature on every edge have maximum degree at most $9$. Furthermore, if $G$ is maximally outerplanar, then $G$ has…

Combinatorics · Mathematics 2025-10-01 George Brooks , Fadekemi Osaye , Anna Schenfisch , Zhiyu Wang , Jing Yu