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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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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 short proof of a conjecture on the $T_r$-choice number of even cycles [PDF]
, 1998 In this note we prove that the $T_r$-choice number of the cycle $C_{2n}$ is equal to the $T_r$-choice number of the path (tree) on $4n-1$ vertices, i.e. $T_r$-$ch(C_{2n}) = \left\lfloor(2r+2)(4n-2)/(4n-1)\right\rfloor + 1$.
Sitters, R.A.
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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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Colouring the Square of the Cartesian Product of Trees [PDF]
, 2010 We prove upper and lower bounds on the chromatic number of the square of the cartesian product of trees.
Wood, David R.
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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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