Results 1 to 10 of about 1,606 (89)
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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Complexity of locally-injective homomorphisms to tournaments [PDF]
Discrete Mathematics & Theoretical Computer Science, 2018 For oriented graphs $G$ and $H$, a homomorphism $f: G \rightarrow H$ is locally-injective if, for every $v \in V(G)$, it is injective when restricted to some combination of the in-neighbourhood and out-neighbourhood of $v$.
Stefan Bard +4 more
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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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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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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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Coverings of Cubic Graphs and 3-Edge Colorability
Discussiones Mathematicae Graph Theory, 2021 Let h:G˜→Gh:\tilde G \to G be a finite covering of 2-connected cubic (multi)graphs where G is 3-edge uncolorable. In this paper, we describe conditions under which G˜\tilde G is 3-edge uncolorable. As particular cases, we have constructed regular and
Plachta Leonid
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DICHROMATIC NUMBER AND FRACTIONAL CHROMATIC NUMBER
Forum of Mathematics, Sigma, 2016 The dichromatic number of a graph $G$ is the maximum integer $k$
BOJAN MOHAR, HEHUI WU
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On Proper (Strong) Rainbow Connection of Graphs
Discussiones Mathematicae Graph Theory, 2021 A path in an edge-colored graph G is called a rainbow path if no two edges on the path have the same color. The graph G is called rainbow connected if between every pair of distinct vertices of G, there is a rainbow path.
Jiang Hui +3 more
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On Local Antimagic Chromatic Number of Cycle-Related Join Graphs
Discussiones Mathematicae Graph Theory, 2021 An edge labeling of a connected graph G = (V, E) is said to be local antimagic if it is a bijection f : E → {1, . . ., |E|} such that for any pair of adjacent vertices x and y, f+(x) ≠ f+(y), where the induced vertex label f+(x) = Σf(e), with e ranging ...
Lau Gee-Choon, Shiu Wai-Chee, Ng Ho-Kuen
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Coloring subgraphs with restricted amounts of hues
Open Mathematics, 2017 We consider vertex colorings where the number of colors given to specified subgraphs is restricted. In particular, given some fixed graph F and some fixed set A of positive integers, we consider (not necessarily proper) colorings of the vertices of a ...
Goddard Wayne, Melville Robert
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