Skip to main content
Log in

On-line graph coloring of \({\mathbb{P}_5}\)-free graphs

  • Original Article
  • Published:
Acta Informatica Aims and scope Submit manuscript

Abstract

Kierstead et al. (SIAM J Discret Math 8:485–498, 1995) have shown 1 that the competitive function of on-line coloring for \({\mathbb{P}}_5\) -free graphs (i.e., graphs without induced path on 5 vertices) is bounded from above by the exponential function \({\left( 4^{\chi (\mathbb{G})} - 1\right) / 3}\) . No nontrivial lower bound was known. In this paper we show the quadratic lower bound \(\tiny{\left( {\begin{array}{*{20}c} {{\chi ({\mathbb{G}}) + 1}} \\ {2} \\ \end{array} } \right) }\) . More precisely, we prove that \(\tiny{\left( {\begin{array}{*{20}c} {{\chi ({\mathbb{G}}) + 1}} \\ {2} \\ \end{array} } \right) }\) is the exact competitive function for (\({\mathbb{C}}_4, {\mathbb{P}}_5\))-free graphs. In this paper we also prove that 2\(\kappa({\mathbb{G})}\) - 1 is the competitive function of the best clique covering on-line algorithm for (\({\mathbb{C}}_4, {\mathbb{P}}_5\))-free graphs.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Subscribe and save

Springer+ Basic
$34.99 /Month
  • Get 10 units per month
  • Download Article/Chapter or eBook
  • 1 Unit = 1 Article or 1 Chapter
  • Cancel anytime
Subscribe now

Buy Now

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

  • Bacsó G. and Tuza Z. (1990). Dominating cliques in \({\mathbb{P}}_5\) -free graphs Period. Math. Hungar. 21: 303–308

    Article  MATH  MathSciNet  Google Scholar 

  • Bean D.R. (1976). Effective coloration. J. Symb. Log. 41: 469–480

    Article  MATH  MathSciNet  Google Scholar 

  • Cieślik I. (2005). On-line coloring and cliques covering for \({\mathbb{K}}_{s,t}\) -free graphs Acta Inform. 42: 1–22

    Article  MathSciNet  Google Scholar 

  • Cieślik, I., Kozik, M., Micek, P.: On-line coloring of \({\mathbb{I}}_s\) -free graphs and co-planar graphs. In: Computational Logic and Applications, CLA ’05, Discrete Mathematics and Theoretical Computer Science Proceedings AF, pp. 61–68 (2006)

  • Cozzens M. and Kelleher L. (1990). Dominating cliques in graphs. Discret. Math. 86: 101–116

    Article  MathSciNet  Google Scholar 

  • Diestel R. (1997). Graph Theory. Springer, New York

    MATH  Google Scholar 

  • Fouquet J., Giakoumakis V., Maire F. and Thuillier H. (1995). On graphs without \({\mathbb{P}}_5\) and \(\overline{\mathbb{P}}_5\) Discret. Math. 146: 33–44

    Article  MATH  MathSciNet  Google Scholar 

  • Gavril F. (1974). The intersection graphs of subtrees in trees are exactly the chordal graphs. J. Comb. Theory B 16: 261–273

    Article  MathSciNet  Google Scholar 

  • Gyárfás A. and Lehel J. (1988). On-line and first fit colorings of graphs. J. Gr. Theory 12: 217–227

    Article  MATH  Google Scholar 

  • Gyárfás A. and Lehel J. (1991). Effective on-line coloring of \({\mathbb{P}}_5\)-free graphs Combinatorica 11: 181–184

    Article  MATH  MathSciNet  Google Scholar 

  • Gyárfás A., Király Z. and Lehel J. (1999). On-line 3-chromatic Graphs I. Triangle-Free Graphs. SIAM J. Discret. Math. 12(3): 385–411

    Article  MATH  Google Scholar 

  • Kierstead H.A. and Trotter W.T. (1981). An extremal problem in recursive combinatorics. Congr. Numer. 33: 143–153

    MathSciNet  Google Scholar 

  • Kierstead H.A., Penrice S.G. and Trotter W.T. (1995). On-line and first-fit coloring of graphs which do not induce \({\mathbb{P}_5}\) SIAM J. Discret. Math. 8: 485–498

    Article  MATH  MathSciNet  Google Scholar 

  • Ślusarek M. (1995). Optimal on-line coloring of circular arc graphs. Inform. Theor. Appl. 29: 423–429

    Google Scholar 

Download references

Author information

Authors and Affiliations

Authors

Corresponding author

Correspondence to Iwona Cieślik.

Rights and permissions

Reprints and permissions

About this article

Cite this article

Cieślik, I. On-line graph coloring of \({\mathbb{P}_5}\)-free graphs. Acta Informatica 45, 79–91 (2008). https://doi.org/10.1007/s00236-007-0064-x

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s00236-007-0064-x

Keywords