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Polynomial \(\chi \)-Binding Functions and Forbidden Induced Subgraphs: A Survey

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Abstract

A graph G with clique number \(\omega (G)\) and chromatic number \(\chi (G)\) is perfect if \(\chi (H)=\omega (H)\) for every induced subgraph H of G. A family \({\mathcal {G}}\) of graphs is called \(\chi \)-bounded with binding function f if \(\chi (G') \le f(\omega (G'))\) holds whenever \(G \in {\mathcal {G}}\) and \(G'\) is an induced subgraph of G. In this paper we will present a survey on polynomial \(\chi \)-binding functions. Especially we will address perfect graphs, hereditary graphs satisfying the Vizing bound (\(\chi \le \omega +1\)), graphs having linear \(\chi \)-binding functions and graphs having non-linear polynomial \(\chi \)-binding functions. Thereby we also survey polynomial \(\chi \)-binding functions for several graph classes defined in terms of forbidden induced subgraphs, among them \(2K_2\)-free graphs, \(P_k\)-free graphs, claw-free graphs, and \({ diamond}\)-free graphs.

Families of\(\chi \)-bound graphs are natural candidates for polynomial approximation algorithms for the vertex coloring problem. (András Gyárfás [42])

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Notes

  1. The essential ingredients of the proof of the result that a connected \((2K_2, { claw})\)-free graph G with independence number \(\alpha (G) \ge 3\) is perfect, are Ben Rebea’s Lemma [31] asserting for a connected \({ claw}\)-free graph with \(\alpha (G) \ge 3\), that if G contains an odd \({ antihole}\), then it contains a \({ hole}\) of length five, and the following characterisation. Under the additional assumption that G is Y-free, all graphs Y such that every connected \(({ claw},Y)\)-free graph is perfect are characterised . Namely, the following three statements are equivalent: (i) every connected \(({ claw},Y)\)-free graph G with \(\alpha (G)\ge 2\) (with \(\alpha (G)\ge 3\)) distinct from an odd cycle is perfect. (ii) Every connected \(({ claw},Y)\)-free graph G with \(\alpha (G)\ge 2\) (with \(\alpha (G)\ge 3\)) distinct from an odd cycle is \(\omega (G)\)-colourable. (iii) Y is isomorphic to \(P_4\) (to \(P_5\)) or to \({ paw}\) (to \({ hammer}\)) or to an induced subgraph of \(P_4\) or \({ paw}\) (of \(P_5\) or \({ hammer}\)) (see Fig. 2).

  2. In a subsequent section we will recall this graph family and remark that the smallest \(\chi \)-binding function \(f^*_{P_4\cup K_1}\) satisfies \(f^*_{P_4\cup K_1}(\omega )\ge \frac{R(3,\omega +1 )}{2}\). Here R(pq) is the Ramsey number, that is the smallest integer n such that every graph G of order at least n contains an independent set with p vertices or a clique with q vertices.

  3. A graph is called perfectly divisible if every induced subgraph H of G contains a set X of vertices such that X meets all largest cliques of H and X induces a perfect graph (cf. Sect. 5). Observe that every \((P_4\cup K_1)\)-free graph is perfectly divisible.

  4. Since due to Strong Perfect Graph Theorem a graph is perfect if and only if it contains neither an odd cycle of length at least five nor its complement, we observe that \(P_4\)-free graphs is the unique graph family defined in terms of one forbidden induced subgraph being perfect, thus having \(\chi \)-binding function \(f(\omega )=\omega \). Furthermore there exists no pair of forbidden induced graphs ensuring perfectness, which generalizes \(P_4\)-free graphs. Studying triples easily yields only the saturated triple \((C_5, P_6, \overline{P_6})\), i.e. every \((C_5, P_6, \overline{P_6})\)-free graph is perfect. The sequence can easily be extended, e. g. \((C_5, C_7, P_8, \overline{P_6})\), \((C_5, P_6, \overline{C_7}, \overline{P_8})\),...yielding all saturated k-tuples with \(k>2\) of (connected) forbidden induced subgraphs which imply the absence of all odd \({ hole}\) or \({ antihole}\) of length at least five.

  5. Atminas, Lozin and Zamaraev [2] examined structural properties of \(({ claw, co}\)-claw)-free graphs.

  6. Chudnovsky et al. [26] gave a decomposition result concerning \((P_5, \bar{P_5})\)-free graphs.

References

  1. Addario-Berry, L., Chudnovsky, M., Havet, F., Reed, B., Seymour, P.: Bisimplicial vertices in even-hole-free graphs. J. Combin. Theory B 98, 1119–1164 (2008)

    Article  MathSciNet  MATH  Google Scholar 

  2. Atminas, A., Lozin, V., Zamaraev, V.: Linear Ramsey Numbers. Lecture Notes in Computer Science, pp. 26–38 (2018)

  3. Bacsó, G., Tuza, Zs: Dominating cliques in \(P_5\)-free graphs. Period. Math. Hungar. 21(3), 303–308 (1990)

    Article  MathSciNet  MATH  Google Scholar 

  4. Beineke, L.W.: Derived graphs and digraphs. In: Sachs, H. (ed.) Beiträge zur Graphentheorie, pp. 17–33. Teubner, Leipzig (1968)

    Google Scholar 

  5. Berge, C.: Perfect Graphs, Six Papers on Graph Theory, pp. 1–21. Indian Statistical Institute, Calcutta (1963)

    Google Scholar 

  6. Bharathi, A., Choudum, S.A.: Colouring of \((P_3 \cup P_2)\)-free graphs. Graphs Combin. 34(1), 97–107 (2018)

    Article  MathSciNet  MATH  Google Scholar 

  7. Blázsik, Z., Hujter, M., Pluhár, A., Tuza, Zs: Graphs with no induced \(C_4\). Discrete Math. 115, 51–55 (1993)

    Article  MathSciNet  MATH  Google Scholar 

  8. Bollobás, B.: The independence ratio of regular graphs. Proc. Am. Math. Soc. 83(2), 433–436 (1981)

    Article  MathSciNet  MATH  Google Scholar 

  9. Brandstädt, A., Le, V.B., Spinrad, J.P.: Graph Classes: A Survey, SIAM Monographs on Discrete Mathematics and Applications. SIAM, Philadelphia (1999)

    Book  Google Scholar 

  10. Brandt, S.: Triangle-free graphs and forbidden subgraphs. Discrete Math. 120, 25–33 (2002)

    Article  MathSciNet  MATH  Google Scholar 

  11. Brause, C., Doan, T.D., Schiermeyer, I.: On the chromatic number of \(P_5, K_{2, t}\) graphs. Electron. Notes Discrete Math. 55, 127–130 (2016)

    Article  MATH  Google Scholar 

  12. Brause, C., Holub, P., Kabela, A., Ryjáček, Z., Schiermeyer, I., Vrána, P.: On forbidden subgraphs for \(K_{1,3}\)-free perfect graphs (2018) (preprint, submitted)

  13. Brause, C., Randerath, B., Schiermeyer, I., Vumar, E.: On the chromatic number of \(2K_2\)-free graphs. Discrete Appl. Math. https://doi.org/10.1016/j.dam.2018.09.030 [Extended abstract in: Bordeaux Graph Workshop, pp. 50–53 (2016)]

  14. Cameron, K., Chaplick, S., Hoáng, C.T.: On the structure of \((pan, even hole)\)-free graphs. J. Graph Theory 87(1), 108–129 (2018)

    Article  MathSciNet  MATH  Google Scholar 

  15. Cameron, K., Huang, S., Merkel, O.: An optimal \(\chi \)-bound for \((P_6,diamond)\)-free graphs (2018) (preprint). arXiv:1809.00739 v1

  16. Cameron, K., da Silva, M., Huang, S., Vušković, K.: Structure and algorithms for \((cap, even hole)\)-free graphs. Discrete Math. 341(2), 463–473 (2018)

    Article  MathSciNet  MATH  Google Scholar 

  17. Choudum, S., Karthick, T.: Maximal cliques in \((P_2 \cup P_3, C_4)\)-free graphs. Discrete Math. 310, 3398–3403 (2010)

    Article  MathSciNet  MATH  Google Scholar 

  18. Choudum, S., Karthick, T., Shalu, M.: Linear chromatic bounds for a subfamily of \(3K_1\)-free graphs. Graphs Combin. 24, 413–428 (2008)

    Article  MathSciNet  MATH  Google Scholar 

  19. Choudum, S., Karthick, T., Shalu, M.: Perfect coloring and linearly \(\chi \)-bound \(P_6\)-free graphs. J. Graph Theory 54, 293–306 (2007)

    Article  MathSciNet  MATH  Google Scholar 

  20. Chudnovsky, M.: The Erdős–Hajnal conjecture—a survey. J. Graph Theory 75, 178–190 (2014)

    Article  MathSciNet  MATH  Google Scholar 

  21. Chudnovsky, M., Seymour, P.: Claw-free graphs VI. Colouring. J. Combin. Theory B 100(6), 560–572 (2010)

    Article  MathSciNet  MATH  Google Scholar 

  22. Chudnovsky, M., Sivaraman, V.: Perfect divisibility and 2-divisibility. J. Graph Theory (2018). https://doi.org/10.1002/jgt.22367

  23. Chudnovsky, M., Robertson, N., Seymour, P., Thomas, R.: The strong perfect graph theorem. Ann. Math. 164, 51–229 (2006)

    Article  MathSciNet  MATH  Google Scholar 

  24. Chudnovsky, M., Robertson, N., Seymour, P., Thomas, R.: \(K_4\)-free graphs with no odd holes. J. Combin. Theory B 100, 313–331 (2010)

    Article  MathSciNet  MATH  Google Scholar 

  25. Chudnovsky, M., Penev, I., Scott, A., Trotignon, N.: Substitution and \(\chi \)-boundness. J. Combin. Theory B 103, 567–586 (2013)

    Article  MATH  Google Scholar 

  26. Chudnovsky, M., Esperet, L., Lemoine, L., Maceli, P., Maffray, F., Penev, I.: Graphs with no induced five-vertex path or antipath. J. Graph Theory 84, 221–232 (2017)

    Article  MathSciNet  MATH  Google Scholar 

  27. Chudnovsky, M., Scott, A., Seymour, P.: Induced subgraphs of graphs with large chromatic number. III. Long holes. Combinatorica 37(6), 1057–1072 (2017)

    Article  MathSciNet  MATH  Google Scholar 

  28. Chudnovsky, M., Scott, A., Seymour, P.: Induced subgraphs of graphs with large chromatic number. XII. Distant stars, (submitted)

  29. Chudnovsky, M., Scott, A., Seymour, P., Spirkl, S.: Induced subgraphs of graphs with large chromatic number. VIII. Long odd holes (submitted)

  30. Chung, F.R.K.: On the covering of graphs. Discrete Math. 30, 89–93 (1980)

    Article  MathSciNet  Google Scholar 

  31. Chvátal, V., Sbihi, N.: Recognizing claw-free perfect graphs. J. Combin. Theory B 44, 154–176 (1988)

    Article  MathSciNet  MATH  Google Scholar 

  32. Conforti, M., Cornuéjols, G., Kapoor, A., Vušković, K.: Even and odd holes in cap-free graphs. J. Graph Theory 30, 289–308 (1999)

    Article  MathSciNet  MATH  Google Scholar 

  33. Dhanalakshmi, S., Sadagopan, N., Manogna, V.: On \(2K_2\)-free graphs—structural and combinatorial view. arXiv:1602.03802v2 [math.CO] (2016)

  34. Erdős, P.: Graph theory and probability. Can. J. Math. 11, 34–38 (1959)

    Article  MathSciNet  MATH  Google Scholar 

  35. Esperet, L., Lemoine, L., Maffray, F., Morel, G.: The chromatic number of \(\{P_5, K_4\}\)-free graphs. Discrete Math. 313, 743–754 (2013)

    Article  MathSciNet  MATH  Google Scholar 

  36. Fan, G., Xu, B., Ye, T., Yu, X.: Forbidden subgraphs and 3-colorings. SIAM J. Discrete Math. 28, 1226–1256 (2017)

    Article  MathSciNet  MATH  Google Scholar 

  37. Fouquet, J.L., Giakoumakis, V., Maire, F., Thuillier, H.: On graphs without \(P_5\) and \({\bar{P}}_5\). Discrete Math. 146, 33–44 (1995)

    Article  MathSciNet  MATH  Google Scholar 

  38. Fraser, D., Hamel, A., Hoàng, C.: On the structure of \((even-hole, kite)\)-free graphs. Graphs Combin. 34, 989–99 (2018)

    Article  MathSciNet  Google Scholar 

  39. Gaspers, S., Huang, S.: \((2P_2,K_4)\)-free graphs are 4-colorable. arXiv:1807.05547v1 [math.CO] (2018)

  40. Golovach, P., Johnson, M., Paulusma, D., Song, J.: A survey on the computational complexity of coloring graphs with forbidden subgraphs. J. Graph Theory 84, 331–363 (2014)

    Article  MathSciNet  MATH  Google Scholar 

  41. Gravier, S., Hoàng, C.T., Maffray, F.: Coloring the hypergraph of maximalcliques of a graph with no long path. Discrete Math. 272, 283–290 (2003)

    Article  MATH  Google Scholar 

  42. Gyárfás, A.: Problems from the world surrounding perfect graphs. In Proc. Int. Conf. on Comb. Analysis and Applications (Pokrzywna, 1985). Zastos. Mat. 19, 413–441 (1987)

    MathSciNet  Google Scholar 

  43. Gyárfás, A., Szemerédi, E., Tuza, Zs: Induced subtrees in graphs of large chromatic number. Discrete Math. 30, 235–244 (1980)

    Article  MathSciNet  MATH  Google Scholar 

  44. Henning, M., Löwenstein, C., Rautenbach, D.: Independent sets and matchings in subcubic graphs. Discrete Math. 312, 1900–1910 (2012)

    Article  MathSciNet  MATH  Google Scholar 

  45. Hoàng, C.: On the structure of (banner, odd hole)-free graphs. J. Graph Theory. https://doi.org/10.1002/jgt.22258

  46. Hoàng, C., McDiarmid, C.: On the divisibility of graphs. Discrete Math. 242, 145–156 (2002)

    Article  MathSciNet  MATH  Google Scholar 

  47. Hougardy, S.: Classes of perfect graphs. Discrete Math. 306, 2529–2571 (2006)

    Article  MathSciNet  MATH  Google Scholar 

  48. Javdekar, M.: Note on Choudom’s chromatic bound for a class of graphs. J. Graph Theory 4, 265–268 (1980)

    Article  MathSciNet  MATH  Google Scholar 

  49. Jensen, T.R., Toft, B.: Graph Colouring Problems. Wiley, New York (1995)

    MATH  Google Scholar 

  50. Karthick, T., Maffray, F.: Vizing bound for the chromatic number on some graph classes. Graphs Combin. 32, 1447–1460 (2016)

    Article  MathSciNet  MATH  Google Scholar 

  51. Karthick, T., Maffray, F.: Square-free graphs with no six-vertex induced path (preprint) (2018). arXiv:1805.05007v1 [cs.DM]

  52. Karthick, T., Maffray, F.: Coloring (gem, co-gem)-free graphs. J. Graph Theory 89, 288–303 (2018)

    Article  MathSciNet  MATH  Google Scholar 

  53. Karthick, T., Mishra, S.: Chromatic bounds for some classes of \(2K_2\)-free graphs. Discrete Math. 341(11), 3079–3088 (2018)

    Article  MathSciNet  MATH  Google Scholar 

  54. Karthick, T., Mishra, S.: On the chromatic number of \((P_6, diamond)\)-free graphs. Graphs Combin. 34, 677–692 (2018)

    Article  MathSciNet  MATH  Google Scholar 

  55. Kierstead, H.: On the chromtaic index of multigraphs without large triangles. J. Combin. Theory B 36, 156–160 (1984)

    Article  MATH  Google Scholar 

  56. Kierstead, H., Penrice, S.: Radius two trees specify \(\chi \)-bounded classes. J. Graph Theory 18, 119–129 (1994)

    Article  MathSciNet  MATH  Google Scholar 

  57. Kierstead, H., Zhu, Y.: Radius three trees in graphs with large chromatic number. SIAM J. Discrete Math. 17, 571–581 (2004)

    Article  MathSciNet  MATH  Google Scholar 

  58. Kim, J.H.: The Ramsey number \(R(3, t)\) has order of magnitude \(t^2/log t\). Random Struct. Algorithms 7, 173–207 (1995)

    Article  MATH  Google Scholar 

  59. Kloks, T., Müller, H., Vušković, K.: Even-hole free graphs that do not contain diamonds: a structure theorem and its consequences. J. Combin. Theory B 99, 733–800 (2009)

    Article  MathSciNet  MATH  Google Scholar 

  60. Lovász, L.: A characterization of perfect graphs. J. Combin. Theory B 13(2), 95–98 (1972)

    Article  MathSciNet  MATH  Google Scholar 

  61. Mohar, B., Thomassen, C.: Graphs on Surfaces. Johns Hopkins University Press, Baltimore (2001)

    MATH  Google Scholar 

  62. Molloy, M., Reed, B.: Graph Colourings and the Probabilistic Method. Algorithms Comb., vol. 23. Springer, Berlin (2002)

    Book  MATH  Google Scholar 

  63. Mycielski, J.: Sur le coloriage des graphes. Colloq. Math. 3, 161–162 (1955)

    Article  MathSciNet  MATH  Google Scholar 

  64. Olariu, S.: Paw-free graphs. Inf. Process. Lett. 28, 53–54 (1988)

    Article  MathSciNet  MATH  Google Scholar 

  65. Ramirez-Alfonsin, J.L., Reed, B.: Perfect Graphs. Springer, Berlin (2001)

    MATH  Google Scholar 

  66. Randerath, B.: The Vizing bound for the chromatic number based on forbidden pairs, Ph.D. thesis. RWTH Aachen, Shaker Verlag (1998)

  67. Randerath, B.: \(3\)-Colorability and forbidden subgraphs. I: chracterizing pairs. Discrete Math. 276, 313–325 (2004)

    Article  MathSciNet  MATH  Google Scholar 

  68. Randerath, B., Schiermeyer, I., Tewes, M.: \(3\)-Colorability and forbidden subgraphs. II: polynomial algorithms. Discrete Math. 251(1–3), 137–153 (2002)

    Article  MathSciNet  MATH  Google Scholar 

  69. Randerath, B., Schiermeyer, I.: Vertex colouring and forbidden subgraphs—a survey. Graphs Combin. 20(1), 1–40 (2004)

    Article  MathSciNet  MATH  Google Scholar 

  70. Roussel, F., Rusu, I., Thuillier, H.: The Strong Perfect Graph Conjecture: 40 years of attempts, and its resolution. Discrete Math. 309, 6092–6113 (2009)

    Article  MathSciNet  MATH  Google Scholar 

  71. Schiermeyer, I.: Chromatic number of \(P_5\)-free graphs: Reed’s conjecture. Discrete Math. 339(7), 1940–1943 (2016)

    Article  MathSciNet  MATH  Google Scholar 

  72. Schiermeyer, I.: On the chromatic number of \((P_5, windmill)\)-free graphs. Opusc. Math. 37(4), 609–615 (2017)

    Article  MATH  Google Scholar 

  73. Scott, A.D.: Induced trees in graphs of large chromatic number. J. Graph Theory 24, 297–311 (1997)

    Article  MathSciNet  MATH  Google Scholar 

  74. Scott, A., Seymour, P.: Induced subgraphs of graphs with large chromatic number. I. Odd holes. J. Combin. Theory B 121, 68–84 (2016)

    Article  MathSciNet  MATH  Google Scholar 

  75. Scott, A., Seymour, P.: Induced subgraphs of graphs with large chromatic number. XIII. New Brooms (submitted)

  76. Sivaraman, V.: Some problems on induced subgraphs. Discrete Appl. Math. 236, 422–427 (2018)

    Article  MathSciNet  MATH  Google Scholar 

  77. Sumner, D.P.: Subtrees of a graph and the chromatic number. In: Chartrand, G. (ed.) The Theory and Applications of Graphs, 4th Int. Conf., Kalamazoo/Mich., pp. 557–576. Wiley, New York (1980)

    Google Scholar 

  78. Truemper, K.: Alpha-balanced graphs and matrices and GF(3)-representability of matroids. J. Combin. Theory B 32, 112–139 (1982)

    Article  MathSciNet  MATH  Google Scholar 

  79. Tuza, Z.: Graph colorings with local constraints—a survey. Discuss. Math. Graph Theory 17, 161–228 (1997)

    Article  MathSciNet  MATH  Google Scholar 

  80. Vušković, K.: Even-hole free graphs: a survey. Appl. Anal. Discrete Math. 4, 219–240 (2010)

    Article  MathSciNet  MATH  Google Scholar 

  81. Wagon, S.: A bound on the chromatic number of graphs without certain induced subgraphs. J. Combin. Theory B 29, 345–346 (1980)

    Article  MathSciNet  MATH  Google Scholar 

  82. Yuditsky, Y.: Workshop “New trends in graph colouring” at BIRS (private communication) (2016)

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We thank an anonymous reviewer for several valuable comments.

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Schiermeyer, I., Randerath, B. Polynomial \(\chi \)-Binding Functions and Forbidden Induced Subgraphs: A Survey. Graphs and Combinatorics 35, 1–31 (2019). https://doi.org/10.1007/s00373-018-1999-0

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