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A Unified Erdős–Pósa Theorem for Constrained Cycles

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Abstract

A (Γ1,Γ2)-labeled graph is an oriented graph with its edges labeled by elements of the direct sum of two groups Γ1,Γ2. A cycle in such a labeled graph is (Γ1,Γ2)-non-zero if it is non-zero in both coordinates. Our main result is a generalization of the Flat Wall Theorem of Robertson and Seymour to (Γ1,Γ2)-labeled graphs. As an application, we determine all canonical obstructions to the Erdős–Pósa property for (Γ1,Γ2)-non-zero cycles in (Γ1,Γ2)-labeled graphs. The obstructions imply that the half-integral Erdős–Pósa property always holds for (Γ1,Γ2)-non-zero cycles.

Moreover, our approach gives a unified framework for proving packing results for constrained cycles in graphs. For example, as immediate corollaries we recover the Erdős–Pósa property for cycles and S-cycles and the half-integral Erdős–Pósa property for odd cycles and odd S-cycles. Furthermore, we recover Reed's Escher-wall Theorem.

We also prove many new packing results as immediate corollaries. For example, we show that the half-integral Erdős–Pósa property holds for cycles not homologous to zero, odd cycles not homologous to zero, and S-cycles not homologous to zero. Moreover, the (full) Erdős–Pósa property holds for S1-S2-cycles and cycles not homologous to zero on an orientable surface. Finally, we also describe the canonical obstructions to the Erdős–Pósa property for cycles not homologous to zero and for odd S-cycles.

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References

  1. E. Birmelé, J.A. Bondy and B. Reed: The Erdős–Pósa property for long circuits, Combinatorica 27 (2007), 135–145.

    Article  MathSciNet  MATH  Google Scholar 

  2. H. Bruhn, F. Joos and O. Schaudt: Long cycles through prescribed vertices have the Erdős–Pósa property, to appear in J. Graph Theory.

  3. M. Chudnovsky, J. Geelen, B. Gerards, L. Goddyn, M. Lohman and P. Seymour: Non-zero A-paths in group-labelled graphs, Combinatorica 26 (2006), 521–532.

    Article  MathSciNet  MATH  Google Scholar 

  4. R. P. Dilworth: A decomposition theorem for partially ordered sets, Ann. of Math. (2) 51 (1950), 161–166.

    Article  MathSciNet  MATH  Google Scholar 

  5. P. Erdős and L. Pósa: On the maximal number of disjoint circuits of a graph, Publ. Math. Debrecen 9 (1962), 3–12.

    MathSciNet  MATH  Google Scholar 

  6. P. Erdős and G. Szekeres: A combinatorial problem in geometry, Compositio Math. 2 (1935), 463–470.

    MathSciNet  MATH  Google Scholar 

  7. S. Fiorini and A. Herinckx: A tighter Erdős–Pósa function for long cycles, J. Graph Theory 77 (2013), 111–116.

    Article  MATH  Google Scholar 

  8. J. Geelen and B. Gerards: Excluding a group-labelled graph, J. Combin. Theory Ser. B 99 (2009), 247–253.

    Article  MathSciNet  MATH  Google Scholar 

  9. J. Geelen, B. Gerards, B. Reed, P. Seymour and A. Vetta: On the odd-minor variant of Hadwiger's conjecture, J. Combin. Theory (Series B) 99 (2009), 20–29.

    Article  MathSciNet  MATH  Google Scholar 

  10. T. Huynh: The linkage problem for group-labelled graphs, PhD thesis, University of Waterloo, 2009.

    Google Scholar 

  11. N. Kakimura, K. Kawarabayashi and D. Marx: Packing cycles through prescribed vertices, J. Combin. Theory Ser. B 101 (2011), 378–381.

    Article  MathSciNet  MATH  Google Scholar 

  12. K. Kawarabayashi and N. Kakimura: Half-integral packing of odd cycles through prescribed vertices, Combinatorica 33 (2014), 549–572.

    MathSciNet  MATH  Google Scholar 

  13. K. Kawarabayashi, R. Thomas and P. Wollan: A new proof of the Flat Wall Theorem, J. Combin. Theory Ser. B 129 (2018), 204–238.

    Article  MathSciNet  MATH  Google Scholar 

  14. D. Lokshtanov, M. S. Ramanujan and S. Saurabh: The half-integral Erdős–Pósa property for non-null cycles, arXiv:1703.02866, 2017.

    Google Scholar 

  15. M. Pontecorvi and P. Wollan: Disjoint cycles intersecting a set of vertices, J. Combin. Theory (Series B) 102 (2012), 1134–1141.

    Article  MathSciNet  MATH  Google Scholar 

  16. B. Reed: Mangoes and blueberries, Combinatorica 19 (1999), 267–296.

    Article  MathSciNet  MATH  Google Scholar 

  17. N. Robertson and P. Seymour: Graph minors. X. Obstructions to tree-decomposition, J. Combin. Theory Ser. B 52 (1991), 153–190.

    Article  MathSciNet  MATH  Google Scholar 

  18. N. Robertson and P. Seymour: Graph minors. XIII. The disjoint paths problem, J. Combin. Theory Ser. B 63 (1995), 65–110.

    Article  MathSciNet  MATH  Google Scholar 

  19. C. Thomassen: On the presence of disjoint subgraphs of a specified type, J. Graph Theory 12 (1988), 101–111.

    Article  MathSciNet  MATH  Google Scholar 

  20. P. Wollan: Packing cycles with modularity constraints, Combinatorica 31 (2011), 95–126.

    Article  MathSciNet  MATH  Google Scholar 

  21. T. Zaslavsky: Biased graphs. I. Bias, balance, and gains, J. Combin. Theory Ser. B 47 (1989), 32–52.

    Article  MathSciNet  MATH  Google Scholar 

  22. T. Zaslavsky: Biased graphs. II. The three matroids, J. Combin. Theory Ser. B 51 (1991), 46–72.

    Article  MathSciNet  MATH  Google Scholar 

Download references

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Correspondence to Tony Huynh.

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This research is supported by the European Research Council under the European Unions Seventh Framework Programme (FP7/2007-2013)/ERC Grant Agreement no. 279558.

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Huynh, T., Joos, F. & Wollan, P. A Unified Erdős–Pósa Theorem for Constrained Cycles. Combinatorica 39, 91–133 (2019). https://doi.org/10.1007/s00493-017-3683-z

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  • DOI: https://doi.org/10.1007/s00493-017-3683-z

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