Results 21 to 30 of about 262 (128)
List Edge Coloring of Planar Graphs without 6-Cycles with Two Chords
Discussiones Mathematicae Graph Theory, 2021 A graph G is edge-L-colorable if for a given edge assignment L = {L(e) : e ∈ E(G)}, there exists a proper edge-coloring φ of G such that φ(e) ∈ L(e) for all e ∈ E(G). If G is edge-L-colorable for every edge assignment L such that |L(e)| ≥ k for all e ∈ E(
Hu Linna, Sun Lei, Wu Jian-Liang
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Facial Rainbow Coloring of Plane Graphs
Discussiones Mathematicae Graph Theory, 2019 A vertex coloring of a plane graph G is a facial rainbow coloring if any two vertices of G connected by a facial path have distinct colors. The facial rainbow number of a plane graph G, denoted by rb(G), is the minimum number of colors that are necessary
Jendroľ Stanislav, Kekeňáková Lucia
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T-Colorings, Divisibility and the Circular Chromatic Number
Discussiones Mathematicae Graph Theory, 2021 Let T be a T -set, i.e., a finite set of nonnegative integers satisfying 0 ∈ T, and G be a graph. In the paper we study relations between the T -edge spans espT (G) and espd⊙T(G), where d is a positive integer and d⊙T={0≤t≤d(maxT+1):d|t⇒t/d∈T}.d \odot T =
Janczewski Robert +2 more
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Hardness Results and Spectral Techniques for Combinatorial Problems on Circulant Graphs [PDF]
, 1998 We show that computing (and even approximating) MAXIMUM CLIQUE and MINIMUM GRAPH COLORING for circulant graphs is essentially as hard as in the general case.
Ivan Gerace +8 more
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Oriented Chromatic Number of Cartesian Products and Strong Products of Paths
Discussiones Mathematicae Graph Theory, 2019 An oriented coloring of an oriented graph G is a homomorphism from G to H such that H is without selfloops and arcs in opposite directions. We shall say that H is a coloring graph.
Dybizbański Janusz, Nenca Anna
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The List Edge Coloring and List Total Coloring of Planar Graphs with Maximum Degree at Least 7
Discussiones Mathematicae Graph Theory, 2020 A graph G is edge k-choosable (respectively, total k-choosable) if, whenever we are given a list L(x) of colors with |L(x)| = k for each x ∈ E(G) (x ∈ E(G) ∪ V (G)), we can choose a color from L(x) for each element x such that no two adjacent (or ...
Sun Lin +3 more
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Packing Coloring of Some Undirected and Oriented Coronae Graphs
Discussiones Mathematicae Graph Theory, 2017 The packing chromatic number χρ(G) of a graph G is the smallest integer k such that its set of vertices V(G) can be partitioned into k disjoint subsets V1, . . . , Vk, in such a way that every two distinct vertices in Vi are at distance greater than i in
Laïche Daouya +2 more
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On the logical strengths of partial solutions to mathematical problems
Transactions of the London Mathematical Society, Volume 4, Issue 1, Page 30-71, December 2017., 2017 Abstract We use the framework of reverse mathematics to address the question of, given a mathematical problem, whether or not it is easier to find an infinite partial solution than it is to find a complete solution. Following Flood [‘Reverse mathematics and a Ramsey‐type König's lemma’, J. Symb. Log.
Laurent Bienvenu +2 more
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On parsimonious edge-colouring of graphs with maximum degree three [PDF]
, 2013 Revised version submitted to Graphs and CombinatoricsInternational audienceIn a graph $G$ of maximum degree $\Delta$ let $\gamma$ denote the largest fraction of edges that can be $\Delta$ edge-coloured.
Fouquet, Jean-Luc, Vanherpe, Jean-Marie
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Discussiones Mathematicae Graph Theory, 2018 In 1940, Lebesgue proved that every 3-polytope contains a 5-vertex for which the set of degrees of its neighbors is majorized by one of the following sequences: (6, 6, 7, 7, 7), (6, 6, 6, 7, 9), (6, 6, 6, 6, 11), (5, 6, 7, 7, 8), (5, 6, 6, 7, 12), (5, 6,
Borodin Oleg V. +2 more
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