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An Oriented 6-Coloring of Planar Graphs with Girth at Least 9

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Abstract

We prove that every oriented graph with a maximum average degree less than 18/7 admits a homomorphism into \(P_{7}^{*}\), the Paley tournament of order seven with one vertex deleted. In particular, every oriented planar graph of girth at least 9 has a homomorphism into \(P_{7}^{*}\), whence every planar graph of girth at least 9 has oriented chromatic number at most 6.

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References

  1. Borodin, O.V.: On acyclic colorings of planar graphs. Discrete Math. 25, 211–236 (1979)

    Article  MathSciNet  MATH  Google Scholar 

  2. Borodin, O.V., Ivanova, A.O.: An oriented 7-coloring of planar graphs with girth at least 7. Sib. Electron. Math. Rep. 2, 222–229 (2005)

    MathSciNet  MATH  Google Scholar 

  3. Borodin, O.V., Ivanova, A.O., Kostochka, A.V.: Oriented 5-coloring of vertices in sparse graphs. (Russian) Diskretn. Anal. Issled. Oper. Ser. 1, 13(1), 16–32 (2006); translation in J. Appl. Ind. Math. 1(1), 9–17 (2007)

  4. Borodin, O.V., Kostochka, A.V., Nešetřil, J., Raspaud, A., Sopena, E.: On the maximum average degree and the oriented chromatic number of a graph. Discrete Math. 206, 77–90 (1999)

    Article  MathSciNet  MATH  Google Scholar 

  5. Marshall, T.H.: Homomorphism bounds for oriented planar graphs of given minimum girth. Graphs Comb. 29, 1489–1499 (2013)

    Article  MathSciNet  MATH  Google Scholar 

  6. Marshall, T.H.: On oriented graphs with certain extension properties. Ars Comb. (To appear)

  7. Nešetřil, J., Raspaud, A., Sopena, E.: Colorings and girth of oriented planar graphs. Discrete Math. 165–166, 519–530 (1997)

    MathSciNet  MATH  Google Scholar 

  8. Ochem, P.: Oriented colorings of triangle-free planar graphs. Inform. Process. Lett. 92, 71–76 (2004)

    Article  MathSciNet  MATH  Google Scholar 

  9. Ochem, P.: Negative results on acyclic improper colorings. Discrete Math. Theor. Comput. Sci. Proc. AE. 357–362 (2005)

  10. Ochem, P., Pinlou, A.: Oriented colorings of partial 2-trees. Inform. Process. Lett. 108(2), 82–86 (2008)

    Article  MathSciNet  MATH  Google Scholar 

  11. Ochem, P., Pinlou, A.: Oriented coloring of triangle-free planar graphs and 2-outerplanar graphs. Electron. Note. Discrete Math. 37, 123–128 (2011)

    Article  MathSciNet  MATH  Google Scholar 

  12. Pinlou, A.: An oriented coloring of planar graphs with girth at least five. Discrete Math. 309, 2108–2118 (2009)

    Article  MathSciNet  MATH  Google Scholar 

  13. Raspaud, A., Sopena, E.: Good and semi-strong colorings of oriented planar graphs. Inform. Proc. Lett. 51, 171–174 (1994)

    Article  MathSciNet  MATH  Google Scholar 

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Marshall, T.H. An Oriented 6-Coloring of Planar Graphs with Girth at Least 9. Graphs and Combinatorics 32, 1101–1116 (2016). https://doi.org/10.1007/s00373-015-1612-8

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  • DOI: https://doi.org/10.1007/s00373-015-1612-8

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