Results 21 to 30 of about 17,567 (164)
On edge colorings of 1-planar graphs [PDF]
Information Processing Letters, 2011 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Xin Zhang 0017, Jianliang Wu 0001
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A First Order Logic Definition of Beyond-Planar Graphs
Journal of Graph Algorithms and Applications, 2018 Beyond-planarity is a collective term for classes of graphs that extend the planar graphs and are defined by drawings with restrictions on crossings. Examples are 1-planar, fan-planar, fan-crossing free, and quasi-planar graphs. We define these and other
Franz Brandenburg
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Drawing Outer 1-planar Graphs with Few Slopes
Journal of Graph Algorithms and Applications, 2015 A graph is outer 1-planar if it admits a drawing where each vertex is on the outer face and each edge is crossed by at most another edge. Outer 1-planar graphs are a superclass of the outerplanar graphs and a subclass of the planar partial 3-trees.
Emilio Di Giacomo +2 more
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Acyclic colouring of 1-planar graphs
Discrete Applied Mathematics, 2001 A graph is said to be 1-planar if it can be embedded into the plane so that each of its edges is crossed by at most one other edge. A coloring of the vertices of a graph is said to be acyclic if every cycle contains at least three colors. The acyclic chromatic number \(a(G)\) of a graph \(G\) is the minimal \(k\) such that \(G\) admits an acyclic \(k\)-
Oleg V. Borodin +3 more
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On Aligned Bar 1-Visibility Graphs
Journal of Graph Algorithms and Applications, 2017 A graph is called a bar 1-visibility graph if its vertices can be represented as horizontal segments, called bars, and each edge corresponds to a vertical line of sight which can traverse another bar.
Franz Brandenburg +2 more
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A Note on Universal Point Sets for Planar Graphs
Journal of Graph Algorithms and Applications, 2020 We investigate which planar point sets allow simultaneous straight-line embeddings of all planar graphs on a fixed number of vertices. We first show that at least $(1.293-o(1))n$ points are required to find a straight-line drawing of each $n$-vertex ...
Manfred Scheucher +2 more
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Tuza's Conjecture for Threshold Graphs [PDF]
Discrete Mathematics & Theoretical Computer Science, 2022 Tuza famously conjectured in 1981 that in a graph without k+1 edge-disjoint triangles, it suffices to delete at most 2k edges to obtain a triangle-free graph. The conjecture holds for graphs with small treewidth or small maximum average degree, including
Marthe Bonamy +6 more
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On total colorings of 1-planar graphs [PDF]
Journal of Combinatorial Optimization, 2013 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.
Xin Zhang 0017 +2 more
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On the size of planarly connected crossing graphs
Journal of Graph Algorithms and Applications, 2018 We prove that if an $n$-vertex graph $G$ can be drawn in the plane such that each pair of crossing edges is independent and there is a crossing-free edge that connects their endpoints, then $G$ has $O(n)$ edges.
Eyal Ackerman +2 more
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On (p, 1)-Total Labelling of Some 1-Planar Graphs
Discussiones Mathematicae Graph Theory, 2021 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, it is proved that the (p, 1)-total labelling number (p ≥ 2) of every 1-planar graph G is at most Δ(G) + 2p − 2 provided that Δ (G) ≥
Niu Bei, Zhang Xin
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