Results 51 to 60 of about 1,634 (112)
On Edge Colorings of 1-Planar Graphs without 5-Cycles with Two Chords
Discussiones Mathematicae Graph Theory, 2019 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 every 1-planar graph with maximum degree ∆ ≥ 8 is edge-colorable with ∆ colors if each of its 5-cycles contains ...
Sun Lin, Wu Jianliang
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Realizing the chromatic numbers and orders of spinal quadrangulations of surfaces [PDF]
, 2013 A method is suggested for construction of quadrangulations of the closed orientable surface with given genus g and either (1) with given chromatic number or (2) with given order allowed by the genus g. In particular, N. Hartsfield and G. Ringel's results
Lawrencenko, Serge
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A Survey on the Cyclic Coloring and its Relaxations
Discussiones Mathematicae Graph Theory, 2021 A cyclic coloring of a plane graph is a vertex coloring such that any two vertices incident with the same face receive distinct colors. This type of coloring was introduced more than fifty years ago, and a lot of research in chromatic graph theory was ...
Czap Július +2 more
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A vizing-type theorem for matching forests [PDF]
, 2000 A well known Theorem of Vizing states that one can colour the edges of a graph by $\Delta +\alpha$ colours, such that edges of the same colour form a matching.
Keijsper, J.C.M.
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Vertex coloring of plane graphs with nonrepetitive boundary paths
, 2011 A sequence $s_1,s_2,...,s_k,s_1,s_2,...,s_k$ is a repetition. A sequence $S$ is nonrepetitive, if no subsequence of consecutive terms of $S$ form a repetition. Let $G$ be a vertex colored graph.
Alon +12 more
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On {a, b}-Edge-Weightings of Bipartite Graphs with Odd a, b
Discussiones Mathematicae Graph Theory, 2022 For any S ⊂ ℤ we say that a graph G has the S-property if there exists an S-edge-weighting w : E(G) → S such that for any pair of adjacent vertices u, v we have ∑e∈E(v) w(e) ≠ ∑e∈E(u) w(e), where E(v) and E(u) are the sets of edges incident to v and u ...
Bensmail Julien +2 more
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Cubic graphs with large circumference deficit [PDF]
, 2013 The circumference $c(G)$ of a graph $G$ is the length of a longest cycle. By exploiting our recent results on resistance of snarks, we construct infinite classes of cyclically $4$-, $5$- and $6$-edge-connected cubic graphs with circumference ratio $c(G)/|
Mazák, Ján, Máčajová, Edita
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Discussiones Mathematicae Graph Theory, 2018 Let 𝒫 be an arbitrary class of graphs that is closed under taking induced subgraphs and let 𝒞 (𝒫) be the family of forbidden subgraphs for 𝒫. We investigate the class 𝒫 (k) consisting of all the graphs G for which the removal of no more than k vertices ...
Borowiecki Mieczysław +2 more
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Discussiones Mathematicae Graph Theory, 2022 We introduce a new notion of circular colourings for digraphs. The idea of this quantity, called star dichromatic number χ→*\vec \chi * (D) of a digraph D, is to allow a finer subdivision of digraphs with the same dichromatic number into such which are ...
Hochstättler Winfried, Steiner Raphael
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Rainbow connection in $3$-connected graphs [PDF]
, 2010 An edge-colored graph $G$ is rainbow connected if any two vertices are connected by a path whose edges have distinct colors. The rainbow connection number of a connected graph $G$, denoted by $rc(G)$, is the smallest number of colors that are needed in ...
Li, Xueliang, Shi, Yongtang
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