Results 21 to 30 of about 151,154 (334)
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 ...
Alam, Md. Jawaherul +3 more
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Note on robust coloring of planar graphs [PDF]
Opuscula MathematicaWe consider the robust chromatic number \(\chi_1(G)\) of planar graphs \(G\) and show that there exists an infinite family of planar graphs \(G\) with \(\chi_1(G) = 3\), thus solving a recent problem of Bacsó et al.
František Kardoš +2 more
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Planar cycle-extendable graphs [PDF]
Discrete Mathematics & Theoretical Computer ScienceFor most problems pertaining to perfect matchings, one may restrict attention to matching covered graphs - that is, connected nontrivial graphs with the property that each edge belongs to some perfect matching.
Aditya Y Dalwadi +3 more
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On the Fiedler value of large planar graphs [PDF]
, 2013 The Fiedler value $\lambda_2$, also known as algebraic connectivity, is the second smallest Laplacian eigenvalue of a graph. We study the maximum Fiedler value among all planar graphs $G$ with $n$ vertices, denoted by $\lambda_{2\max}$, and we show the ...
Alon +25 more
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Planar Transitive Graphs [PDF]
The Electronic Journal of Combinatorics, 2018 We prove that the first homology group of every planar locally finite transitive graph $G$ is finitely generated as an $\Aut(G)$-module and we prove a similar result for the fundamental group of locally finite planar Cayley graphs. Corollaries of these results include Droms's theorem that planar groups are finitely presented and Dunwoody's theorem that
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, 2013 In this paper, the concept of Total semirelib graph of a planar graph is introduced. Authors present a characterization of those graphs whose total semirelib graphs are planar, outer planar, Eulerian, hamiltonian with crossing number ...
Goudar, Venkanagouda, Prasad, Manjunath
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Enumeration of labelled 4-regular planar graphs [PDF]
, 2019 We present the first combinatorial scheme for counting labelled 4-regular planar graphs through a complete recursive decomposition. More precisely, we show that the exponential generating function of labelled 4-regular planar graphs can be computed ...
Noy, Marc +2 more
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NP-Completeness Results for Minimum Planar Spanners [PDF]
Discrete Mathematics & Theoretical Computer Science, 1998 For any fixed parameter t greater or equal to 1, a t-spanner of a graph G is a spanning subgraph in which the distance between every pair of vertices is at most t times their distance in G.
Ulrik Brandes, Dagmar Handke
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Negative results on acyclic improper colorings [PDF]
Discrete Mathematics & Theoretical Computer Science, 2005 Raspaud and Sopena showed that the oriented chromatic number of a graph with acyclic chromatic number $k$ is at most $k2^{k-1}$. We prove that this bound is tight for $k \geq 3$.
Pascal Ochem
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A Note on Edge-Group Choosability of Planar Graphs without 5-Cycles
Journal of Mathematics, 2020 This paper is devoted to a study of the concept of edge-group choosability of graphs. We say that G is edge-k-group choosable if its line graph is k-group choosable.
Amir Khamseh
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