Results 31 to 40 of about 267 (133)
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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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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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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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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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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On the Palette Index of Complete Bipartite Graphs
Discussiones Mathematicae Graph Theory, 2018 The palette of a vertex x of a graph G determined by a proper edge colouring φ of G is the set {φ(xy) : xy ∈ E(G)} and the diversity of φ is the number of different palettes determined by φ. The palette index of G is the minimum of diversities of φ taken
Horňák Mirko, Hudák Juraj
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Малки неравномерни хиперграфи без свойство B
, 2023 [Cherkashin Danila; Черкашин Данила]2020 Mathematics Subject Classification: 05C15 ...
Cherkashin, Danila
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On Color Energy of Few Classes of Bipartite Graphs and Corresponding Color Complements [PDF]
, 2019 For a given colored graph G, the color energy is defined as Ec(G) = Σλi, for i = 1, 2,…., n; where λi is a color eigenvalue of the color matrix of G, Ac (G) with entries as 1, if both the corresponding vertices are neighbors and have different colors; -1,
Prajakta Bharat Joshi, Mayamma Joseph
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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
wiley +1 more source