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Related papers: Light edges in 1-planar graphs of minimum degree 3

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It is well-known that 1-planar graphs have minimum degree at most 7, and not hard to see that some 1-planar graphs have minimum degree exactly 7. In this note we show that any such 1-planar graph has at least 24 vertices, and this is tight.

Combinatorics · Mathematics 2019-10-07 Therese Biedl

A graph is {\em $1$-planar} if it can be drawn in the plane such that every edge crosses at most one other edge. A connected graph $H$ is {\em strongly light} in a family of graphs $\mathfrak{G}$, if there exists a constant $\lambda$, such…

Combinatorics · Mathematics 2018-11-20 Tao Wang

A 1-planar graph is a graph which has a drawing on the plane such that each edge is crossed at most once. If a 1-planar graph is drawn in that way, the drawing is called a {\it 1-plane graph}. A graph is maximal 1-plane (or 1-planar) if no…

Combinatorics · Mathematics 2025-05-01 Zhangdong Ouyang , Yuanqiu Huang , Licheng Zhang , Fengming Dong

A graph is called 1-planar if it can be drawn on the plane so that each edge is crossed by at most one other edge. In this paper, we establish a local property of 1-planar graphs which describes the structure in the neighborhood of small…

Discrete Mathematics · Computer Science 2011-01-04 Xin Zhang , Guizhen Liu , Jian-Liang Wu

A matching of a graph is a set of edges without common end vertex. A graph is called 1-planar if it admits a drawing in the plane such that each edge is crossed at most once. Recently, Biedl and Wittnebel proved that every 1-planar graph…

Combinatorics · Mathematics 2022-07-11 Yuanqiu Huang , Zhangdong Ouyang , Fengming Dong

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 graph is 1-planar if it can be drawn on the plane so that each edge is crossed by at most one other edge. In this note we give examples of class two 1-planar graphs with maximum degree six or seven.

Combinatorics · Mathematics 2011-04-26 Xin Zhang

In 1979, Nishizeki and Baybars showed that every planar graph with minimum degree 3 has a matching of size $\frac{n}{3}+c$ (where the constant $c$ depends on the connectivity), and even better bounds hold for planar graphs with minimum…

Discrete Mathematics · Computer Science 2020-02-21 Therese Biedl , John Wittnebel

We show that every 1-planar graph with minimum degree at least 4 has girth at most $8$, and every 1-planar graph with minimum degree at least 3 has girth at most $198$.

Discrete Mathematics · Computer Science 2020-01-17 François Dross

A graph is 1-planar if it can be drawn on the plane so that each edge is crossed by at most one other edge. In this paper, we confirm the total-coloring conjecture for 1-planar graphs with maximum degree at least 13.

Combinatorics · Mathematics 2013-04-24 Xin Zhang , Jianfeng Hou , Guizhen Liu

A matching is a set of edges without common endpoint. It was recently shown that every 1-planar graph (i.e., a graph that can be drawn in the plane with at most one crossing per edge) that has minimum degree 3 has a matching of size at…

Computational Geometry · Computer Science 2020-03-19 Therese Biedl , Fabian Klute

A graph is called 1-planar if it can be drawn in the plane so that each of its edges is crossed by at most one other edge. In this paper we decompose the set of all 1-planar graphs into three classes $\mathcal C_0, \mathcal C_1$ and…

Combinatorics · Mathematics 2017-03-16 Július Czap , Peter Šugerek

A connected graph $G$ with at least two vertices is matching covered if each of its edges lies in a perfect matching. A matching covered graph is minimal if the removal of any edge results in a graph that is no longer matching covered. An…

Combinatorics · Mathematics 2026-04-02 Xiaoling He , Fuliang Lu , Heping Zhang

A graph is $k$-planar if it can be drawn in the plane such that no edge is crossed more than $k$ times. While for $k=1$, optimal $1$-planar graphs, i.e., those with $n$ vertices and exactly $4n-8$ edges, have been completely characterized,…

Computational Geometry · Computer Science 2017-03-21 Michael A. Bekos , Michael Kaufmann , Chrysanthi N. Raftopoulou

In octilinear drawings of planar graphs, every edge is drawn as an alternating sequence of horizontal, vertical and diagonal ($45^\circ$) line-segments. In this paper, we study octilinear drawings of low edge complexity, i.e., with few…

Data Structures and Algorithms · Computer Science 2014-08-27 Michael A. Bekos , Martin Gronemann , Michael Kaufmann , Robert Krug

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

A graph is 1-planar if it can be drawn on a plane so that each edge is crossed by at most one other edge. In this paper, we first give a useful structural theorem for 1-planar graphs, and then apply it to the list edge and list total…

Combinatorics · Mathematics 2019-12-17 Xin Zhang , Bei Niu , Jiguo Yu

A 1-plane graph is a graph together with a drawing in the plane in such a way that each edge is crossed at most once. A 1-plane graph is maximal if no edge can be added without violating either 1-planarity or simplicity. Let $m(n)$ denote…

Combinatorics · Mathematics 2025-02-18 Yuanqiu Huang , Zhangdong Ouyang , Licheng Zhang , Fengming Dong

A graph is 1-planar if it can be drawn on the plane so that each edge is crossed by no more than one other edge (and any pair of crossing edges cross only once). A non-1-planar graph $G$ is minimal if the graph $G-e$ is 1-planar for every…

Combinatorics · Mathematics 2011-10-24 Vladimir P. Korzhik , Bojan Mohar

A graph is 1-planar if it can be drawn in the plane so that each edge is crossed at most once. However, there are 1-planar graphs which do not admit a straight-line 1-planar drawing. We show that every 1-planar graph has a straight-line…

Computational Geometry · Computer Science 2021-09-07 Franz J. Brandenburg
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