Results 21 to 30 of about 29,089 (268)
Discrete Applied Mathematics, 2017 A graph is NIC-planar if it admits a drawing in the plane with at most one crossing per edge and such that two pairs of crossing edges share at most one common end vertex. NIC-planarity generalizes IC-planarity, which allows a vertex to be incident to at most one crossing edge, and specializes 1-planarity, which only requires at most one crossing per ...
Christian Bachmaier +4 more
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SOME PROPERTIES ON COPRIME GRAPH OF GENERALIZED QUATERNION GROUPS
Barekeng, 2023 A coprime graph is a representation of finite groups on graphs by defining the vertex graph as an element in a group and two vertices adjacent to each other's if and only if the order of the two elements is coprime.
Arif Munandar
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Computational Study on a PTAS for Planar Dominating Set Problem
Algorithms, 2013 The dominating set problem is a core NP-hard problem in combinatorial optimization and graph theory, and has many important applications. Baker [JACM 41,1994] introduces a k-outer planar graph decomposition-based framework for designing polynomial time ...
Qian-Ping Gu, Marjan Marzban
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On Longest Cycles in Essentially 4-Connected Planar Graphs
Discussiones Mathematicae Graph Theory, 2016 A planar 3-connected graph G is essentially 4-connected if, for any 3-separator S of G, one component of the graph obtained from G by removing S is a single vertex.
Fabrici Igor +2 more
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Planar and poly-arc Lombardi drawings
Journal of Computational Geometry, 2018 In Lombardi drawings of graphs, edges are represented as circular arcs and the edges incident on vertices have perfect angular resolution. It is known that not every planar graph has a planar Lombardi drawing.
Christian A. Duncan +5 more
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On certain prime cordial families of graphs
Journal of Taibah University for Science, 2020 Graph labelling is an important tool in modelling real life problems. In the present paper, different graph families are studied for prime cordial labelling.
Nazeran Idrees +3 more
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Fitting Planar Graphs on Planar Maps [PDF]
Journal of Graph Algorithms and Applications, 2014 Graph and cartographic visualization have the common objective to provide intuitive understanding of some underlying data. We consider a problem that combines aspects of both by studying the problem of fitting planar graphs on planar maps. After providing an NP-hardness result for the general decision problem, we identify sufficient conditions so ...
Md. Jawaherul Alam +3 more
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The Electronic Journal of Combinatorics, 2018 A nonplanar graph $G$ is called almost-planar if for every edge $e$ of $G$, at least one of $G\backslash e$ and $G/e$ is planar. In 1990, Gubser characterized 3-connected almost-planar graphs in his dissertation. However, his proof is so long that only a small portion of it was published.
Guoli Ding +2 more
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Sufficient Conditions of 6-Cycles Make Planar Graphs DP-4-Colorable
Mathematics, 2022 In simple graphs, DP-coloring is a generalization of list coloring and thus many results of DP-coloring generalize those of list coloring. Xu and Wu proved that every planar graph without 5-cycles adjacent simultaneously to 3-cycles and 4-cycles is 4 ...
Kittikorn Nakprasit +2 more
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Total Coloring of Claw-Free Planar Graphs
Discussiones Mathematicae Graph Theory, 2022 A total coloring of a graph is an assignment of colors to both its vertices and edges so that adjacent or incident elements acquire distinct colors. Let Δ(G) be the maximum degree of G.
Liang Zuosong
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