2005 European Conference on Combinatorics, Graph Theory and Applications (EuroComb '05)
Stefan Felsner (ed.)
DMTCS Conference Volume AE (2005), pp. 357362
author:  Pascal Ochem 

title:  Negative results on acyclic improper colorings 
keywords:  acyclic colorings, oriented colorings, NPcompleteness 
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
k1
k≥3
. We also show that some improper and/or acyclic
colorings are NPcomplete on a class
C
C
3acyclic colorability
on bipartite planar graphs with maximum degree 4, and
of
4acyclic colorability
on bipartite planar graphs with maximum degree 8.

If your browser does not display the abstract correctly (because of the different mathematical symbols) you may look it up in the PostScript or PDF files.  
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. 357362 
bibtex:  For a corresponding BibTeX entry, please consider our BibTeXfile. 
ps.gzsource:  dmAE0169.ps.gz (63 K) 
pssource:  dmAE0169.ps (159 K) 
pdfsource:  dmAE0169.pdf (157 K) 
The first source gives you the `gzipped' PostScript, the second the plain PostScript and the third the format for the Adobe accrobat reader. Depending on the installation of your web browser, at least one of these should (after some amount of time) pop up a window for you that shows the full article. If this is not the case, you should contact your system administrator to install your browser correctly.
Due to limitations of your local software, the two formats may show up differently on your screen. If eg you use xpdf to visualize pdf, some of the graphics in the file may not come across. On the other hand, pdf has a capacity of giving links to sections, bibliography and external references that will not appear with PostScript.
Automatically produced on Di Sep 27 10:10:02 CEST 2005 by gustedt