Results 51 to 60 of about 20,911 (165)
The fractional chromatic number of the plane [PDF]
Combinatorica, 2016 20 pages, 10 ...
Daniel W. Cranston, Landon Rabern
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On the Chromatic Number of Random Graphs
Journal of Combinatorial Theory, Series B, 2007 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Amin Coja-Oghlan +2 more
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On the complexity of the circular chromatic number [PDF]
Journal of Graph Theory, 2004 AbstractCircular chromatic number, χcis a natural generalization of chromatic number. It is known that it isNP‐hard to determine whether or not an arbitrary graphGsatisfies χ(G)=χc(G). In this paper we prove that this problem isNP‐hard even if the chromatic number of the graph is known. This answers a question of Xuding Zhu.
Hamed Hatami, Ruzbeh Tusserkani
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Coloring Some Finite Sets in ℝn
Discussiones Mathematicae Graph Theory, 2013 This note relates to bounds on the chromatic number χ(ℝn) of the Euclidean space, which is the minimum number of colors needed to color all the points in ℝn so that any two points at the distance 1 receive different colors. In [6] a sequence of graphs Gn
Balogh József +2 more
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Game chromatic number of lexicographic product graphs
AKCE International Journal of Graphs and Combinatorics, 2015 In this paper, we determine the exact values of the game chromatic number of lexicographic product of path P2 with path Pn, star K1,n and wheel Wn. Also we give an upper bound for the game chromatic number of lexicographic product of any two simple ...
R. Alagammai, V. Vijayalakshmi
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On the difference between chromatic number and dynamic chromatic number of graphs
Discrete Mathematics, 2012 zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Arash Ahadi +3 more
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Bipartite Coverings and the Chromatic Number [PDF]
The Electronic Journal of Combinatorics, 2009 Consider a graph $G$ with chromatic number $k$ and a collection of complete bipartite graphs, or bicliques, that cover the edges of $G$. We prove the following two results: $\bullet$ If the bipartite graphs form a partition of the edges of $G$, then their number is at least $2^{\sqrt{\log_2 k}}$.
MUBAYI, D, VISHWANATHAN, S
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Oriented Incidence Colourings of Digraphs
Discussiones Mathematicae Graph Theory, 2019 Brualdi and Quinn Massey [6] defined incidence colouring while study- ing the strong edge chromatic index of bipartite graphs. Here we introduce a similar concept for digraphs and define the oriented incidence chromatic number.
Duffy Christopher +3 more
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The $b$-Chromatic Number and $f$-Chromatic Vertex Number of Regular Graphs
Discret. Appl. Math., 2013 The $b$-chromatic number of a graph $G$, denoted by $b(G)$, is the largest positive integer $k$ such that there exists a proper coloring for G with $k$ colors in which every color class contains at least one vertex adjacent to some vertex in each of the other color classes, such a vertex is called a dominant vertex. The $f$-chromatic vertex number of a
El-Sahili, Amine +3 more
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Hamiltonian Chromatic Number of Trees [PDF]
, 2020 This is a final version appeared in proceedings of RAGT 2019 ...
Devsi Bantva, Samir Vaidya
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