منابع مشابه
Hypergraphs with Zero Chromatic Threshold
Let F be an r-uniform hypergraph. The chromatic threshold of the family of F free, r-uniform hypergraphs is the infimum of all non-negative reals c such that the subfamily of F -free, r-uniform hypergraphs H with minimum degree at least c (|V (H)| r−1 ) has bounded chromatic number. The study of chromatic thresholds of various graphs has a long history, beginning with the early work of Erdős-Si...
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A finite family R of simple Jordan regions in the plane defines a hypergraph H = H(R) where the vertex set of H is R and the hyperedges are all subsets S ⊂ R for which there is a point p such that S = {r ∈ R|p ∈ r}. The chromatic number of H(R) is the minimum number of colors needed to color the members of R such that no hyperedge is monochromatic. In this paper we initiate the study of the chr...
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The theory of mixed hypergraph coloring was first introduced by Voloshin in 1993 and has been growing ever since. The proper coloring of a mixed hypergraph H = (X, C,D) is the coloring of the vertex set X so that no D-hyperedge is monochromatic and no C-hyperedge is polychromatic. A mixed hypergraph with hyperedges of type D, C or B is commonly known as a D, C, or B-hypergraph respectively wher...
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ژورنال
عنوان ژورنال: Graphs and Combinatorics
سال: 2015
ISSN: 0911-0119,1435-5914
DOI: 10.1007/s00373-015-1667-6