Results 11 to 20 of about 26 (26)
Homomorphic Preimages of Geometric Paths
Discussiones Mathematicae Graph Theory, 2018 A graph G is a homomorphic preimage of another graph H, or equivalently G is H-colorable, if there exists a graph homomorphism f : G → H. A geometric graph Ḡ is a simple graph G together with a straight line drawing of G in the plane with the vertices in
Cockburn Sally
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On An Extremal Problem In The Class Of Bipartite 1-Planar Graphs
Discussiones Mathematicae Graph Theory, 2016 A graph G = (V, E) is called 1-planar if it admits a drawing in the plane such that each edge is crossed at most once. In this paper, we study bipartite 1-planar graphs with prescribed numbers of vertices in partite sets.
Czap Július +2 more
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The Crossing Number of The Hexagonal Graph H3,n
Discussiones Mathematicae Graph Theory, 2019 In [C. Thomassen, Tilings of the torus and the Klein bottle and vertex-transitive graphs on a fixed surface, Trans. Amer. Math. Soc. 323 (1991) 605–635], Thomassen described completely all (except finitely many) regular tilings of the torus S1 and the ...
Wang Jing +2 more
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A Note on the Crossing Numbers of 5-Regular Graphs
Discussiones Mathematicae Graph Theory, 2020 The crossing number cr(G) of a graph G is the smallest number of edge crossings in any drawing of G. In this paper, we prove that there exists a unique 5-regular graph G on 10 vertices with cr(G) = 2.
Ouyang Zhangdong
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Discussiones Mathematicae Graph Theory, 2017 We characterize the class L32$L_3^2 $ of intersection graphs of hypergraphs with rank at most 3 and multiplicity at most 2 by means of a finite list of forbidden induced subgraphs in the class of threshold graphs.
Metelsky Yury +2 more
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Requiring that Minimal Separators Induce Complete Multipartite Subgraphs
Discussiones Mathematicae Graph Theory, 2018 Complete multipartite graphs range from complete graphs (with every partite set a singleton) to edgeless graphs (with a unique partite set). Requiring minimal separators to all induce one or the other of these extremes characterizes, respectively, the ...
McKee Terry A.
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Sharp Upper Bounds on the Clar Number of Fullerene Graphs
Discussiones Mathematicae Graph Theory, 2018 The Clar number of a fullerene graph with n vertices is bounded above by ⌊n/6⌋ − 2 and this bound has been improved to ⌊n/6⌋ − 3 when n is congruent to 2 modulo 6.
Gao Yang, Zhang Heping
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The classification of partially symmetric 3-braid links
Open Mathematics, 2015 We classify 3-braid links which are amphicheiral as unoriented links, including a new proof of Birman- Menasco’s result for the (orientedly) amphicheiral 3-braid links. Then we classify the partially invertible 3-braid links.
Stoimenov Alexander
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Archimedean tiling graphs with Gallai’s property
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2017 Gallai in 1966 raised the question about the existence of graphs with the property that every vertex is missed by some longest path. This property will be called Gallai’s property.
Chang Zhikui, Yuan Liping
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Combinatorial Properties and Recognition of Unit Square Visibility Graphs. [PDF]
Discrete Comput Geom, 2023 Casel K +4 more
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