| author: | Pascal Ochem |
|---|---|
| title: | Negative results on acyclic improper colorings |
| keywords: | acyclic colorings, oriented colorings, NP-completeness |
| abstract: |
Raspaud and Sopena showed that the oriented chromatic
number of a graph with acyclic chromatic number
k
is at most
k2
. We prove that this bound is tight for
k-1
k≥3
. We also show that some improper and/or acyclic
colorings are NP-complete on a class
C
C
3-acyclic colorability
on bipartite planar graphs with maximum degree 4, and
of
4-acyclic colorability
on bipartite planar graphs with maximum degree 8.
|
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| reference: | Pascal Ochem (2005), Negative results on acyclic improper colorings, in 2005 European Conference on Combinatorics, Graph Theory and Applications (EuroComb '05), Stefan Felsner (ed.), Discrete Mathematics and Theoretical Computer Science Proceedings AE, pp. 357-362 |
| bibtex: | For a corresponding BibTeX entry, please consider our BibTeX-file. |
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| pdf-source: | dmAE0169.pdf (157 K) |
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