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Degrees and choice numbers

✍ Scribed by Noga Alon


Publisher
John Wiley and Sons
Year
2000
Tongue
English
Weight
74 KB
Volume
16
Category
Article
ISSN
1042-9832

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✦ Synopsis


The choice number ch G of a graph G = V E is the minimum number k such that for every assignment of a list S v of at least k colors to each vertex v ∈ V , there is a proper vertex coloring of G assigning to each vertex v a color from its list S v . We prove that if the minimum degree of G is d, then its choice number is at least 1 2 -o 1 log 2 d, where the o 1 -term tends to zero as d tends to infinity. This is tight up to a constant factor of 2 + o 1 , improves an estimate established by the author, and settles a problem raised by him and Krivelevich.


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