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A Proof of a Conjecture of Ohba

Combinatorics 2014-02-05 v2 Discrete Mathematics
Authors: Jonathan A. Noel , Bruce A. Reed , Hehui Wu
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Abstract

We prove a conjecture of Ohba which says that every graph GG on at most 2χ(G)+12\chi(G)+1 vertices satisfies χℓ(G)=χ(G)\chi_\ell(G)=\chi(G).

Keywords

list coloring choice number chromatic number Ohba's conjecture graph theory

Cite

@article{arxiv.1211.1999,
  title  = {A Proof of a Conjecture of Ohba},
  author = {Jonathan A. Noel and Bruce A. Reed and Hehui Wu},
  journal= {arXiv preprint arXiv:1211.1999},
  year   = {2014}
}

Comments

21 pages

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