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Graphs Without Large Apples and the Maximum Weight Independent Set Problem

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Abstract

An apple A k is the graph obtained from a chordless cycle C k of length k ≥ 4 by adding a vertex that has exactly one neighbor on the cycle. The class of apple-free graphs is a common generalization of claw-free graphs and chordal graphs, two classes enjoying many attractive properties, including polynomial-time solvability of the maximum weight independent set problem. Recently, Brandstädt et al. showed that this property extends to the class of apple-free graphs. In the present paper, we study further generalization of this class called graphs without large apples: these are (A k , A k+1, . . .)-free graphs for values of k strictly greater than 4. The complexity of the maximum weight independent set problem is unknown even for k = 5. By exploring the structure of graphs without large apples, we discover a sufficient condition for claw-freeness of such graphs. We show that the condition is satisfied by bounded-degree and apex-minor-free graphs of sufficiently large tree-width. This implies an efficient solution to the maximum weight independent set problem for those graphs without large apples, which either have bounded vertex degree or exclude a fixed apex graph as a minor.

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References

  1. Alekseev, V.E.: On the number of maximal independent sets in graphs from hereditary classes, Combinatorial-algebraic methods in discrete optimization, University of Nizhny Novgorod, pp. 5–8 (in Russian) (1991)

  2. Alekseev V.E.: A polynomial algorithm for finding the largest independent sets in fork-free graphs. Discret. Appl. Math. 135, 3–16 (2004)

    Article  Google Scholar 

  3. Alekseev, V.E., Lozin, Malyshev, V.D., Milanič, M.: The maximum independent set problem in planar graphs, In: Proceedings of 33rd International Symposium on Mathematical Foundations of Computer Science, Lecture Notes in Computer Science, vol. 5162, pp. 96–107 (2008)

  4. Arnborg S., Proskurowski A.: Linear time algorithms for NP-hard problems restricted to partial k-trees. Discret. Appl. Math. 23, 11–24 (1989)

    Article  MATH  MathSciNet  Google Scholar 

  5. Bodlaender H.L.: A partial k-arboretum of graphs with bounded treewidth. Theor. Comput. Sci. 209, 1–45 (1998)

    Article  MATH  MathSciNet  Google Scholar 

  6. Bodlaender H.L., Thilikos D.M.: Treewidth for graphs with small chordality. Discret. Appl. Math. 79, 45–61 (1997)

    Article  MATH  MathSciNet  Google Scholar 

  7. Brandstädt A., Hoà àng C.: On clique separators, nearly chordal graphs, and the maximum weight stable set problem. Theor. Comput. Sci. 389, 295–306 (2007)

    Article  MATH  Google Scholar 

  8. Brandstädt A., Lozin V., Mosca R.: Independent sets of maximum weight in apple-free graphs. SIAM J. Discret. Math. 24, 239–254 (2010)

    Article  MATH  Google Scholar 

  9. Chudnovsky M., Seymour P.: Clawfree graphs I—orientable prismatic graphs. J. Combin. Theory Ser. B 97, 867–901 (2007)

    Article  MATH  MathSciNet  Google Scholar 

  10. Chudnovsky M., Seymour P.: Clawfree graphs II—nonorientable prismatic graphs. J. Combin. Theory Ser. B 98, 249–290 (2008)

    Article  MATH  MathSciNet  Google Scholar 

  11. Chudnovsky M., Seymour P.: Clawfree graphs III—circular interval graphs. J. Combin. Theory Ser. B 98, 812–834 (2008)

    Article  MATH  MathSciNet  Google Scholar 

  12. Chudnovsky M., Seymour P.: Clawfree graphs IV—decomposition theorem. J. Combin. Theory Ser. B. 98, 839–938 (2008)

    Article  MATH  MathSciNet  Google Scholar 

  13. Chudnovsky M., Seymour P.: Clawfree graphs V—global structure. J. Combin. Theor. Ser. B 98, 1373–1410 (2008)

    Article  MATH  MathSciNet  Google Scholar 

  14. Demaine E.D., Hajiaghayi M.T.: Diameter and treewidth in minor-closed graph families, revisited. Algorithmica 40, 211–215 (2004)

    Article  MATH  MathSciNet  Google Scholar 

  15. Edmonds J.: Maximum matching and a polyhedron with 0,1-vertices. J. Res. Nat. Bur. Standards Sect. B 69, 125–130 (1965)

    Article  MATH  MathSciNet  Google Scholar 

  16. Faenza, Y., Oriolo, G., Stauffer, G.: An algorithmic decomposition of claw-free graphs leading to an O(n 3)-algorithm for the weighted stable set problem. In: Proceedings of Twenty-Second Annual ACM-SIAM Symposium on Discrete Algorithms SODA’, vol. 11, pp. 630–646 (2011)

  17. Farber M., Hujter M., Tuza Z.: An upper bound on the number of cliques in a graph. Networks 23, 207–210 (1993)

    Article  MATH  MathSciNet  Google Scholar 

  18. Frank A.: Some polynomial algorithms for certain graphs and hypergraphs. Congr. Numer. XV, 211–226 (1976)

    Google Scholar 

  19. Gavril F.: Algorithms for minimum coloring, maximum clique, minimum covering by cliques, and maximum independent set of a chordal graph. SIAM J. Comput. 1, 180–187 (1972)

    Article  MATH  MathSciNet  Google Scholar 

  20. Gavril F.: The intersection graphs of subtrees in trees are exactly the chordal graphs. J. Combin. Theor. Ser. B 16, 47–56 (1974)

    Article  MATH  MathSciNet  Google Scholar 

  21. Grötschel, M., Lovász, L., Schrijver, A.: Polynomial algorithms for perfect graphs. Topics on perfect graphs, North-Holland Mathematical Studies, vol. 88, pp. 325–356. North-Holland, Amsterdam (1984)

  22. Hertz A., Werra D.: On the stability number of AH-free graphs. J. Graph. Theor. 17, 53–63 (1993)

    Article  MATH  Google Scholar 

  23. Kamiński M., Lozin V.V., Milanič M.: Recent developments on graphs of bounded clique-width. Discret. Appl. Math. 157, 2747–2761 (2009)

    Article  MATH  Google Scholar 

  24. Lovász L., Plummer M.D.: Matching theory. Ann. Discret. Math. 29, 295–352 (1986)

    Google Scholar 

  25. Lozin V., Milanič M.: A polynomial algorithm to find an independent set of maximum weight in a fork-free graph. J. Discret. Algorithm 6, 595–604 (2008)

    Article  MATH  Google Scholar 

  26. Lozin, V., Milanič, M.: Maximum independent sets in graphs of low degree. In: Proceedings of Eighteenth Annual ACM-SIAM Symposium on Discrete Algorithms SODA’, vol. 07, pp. 874–880 (2007)

  27. Lozin V.V., Mosca R.: Maximum regular induced subgraphs in 2P 3-free graphs. Theor. Comput. Sci. 460, 26–33 (2012)

    Article  MATH  MathSciNet  Google Scholar 

  28. Minty G.J.: On maximal independent sets of vertices in claw-free graphs. J. Combin. Theory Ser. B 28, 284–304 (1980)

    Article  MATH  MathSciNet  Google Scholar 

  29. Nakamura D., Tamura A.: A revision of Minty’s algorithm for finding a maximum weight stable set of a claw-free graph. J. Oper. Res. Soc. Japan 44, 194–204 (2001)

    MATH  MathSciNet  Google Scholar 

  30. Oriolo, G., Pietropaoli, U., Stauffer, G.: A new algorithm for the maximum weighted stable set problem in claw-free graphs. In: Proceedings of IPCO 2008, Bertinoro. Lecture Notes in Computer Science. vol. 5035, pp. 96–107 (2008)

  31. Robertson N.: Graph minors. V. Excluding a planar graph. J. Comb. Theor. B 41, 92–114 (1986)

    Article  MATH  MathSciNet  Google Scholar 

  32. Robertson N., Seymour P.D.: Graph searching and a min-max theorem for tree-width. J. Comb. Theory B 58, 22–33 (1993)

    Article  Google Scholar 

  33. Tarjan R.E.: Decomposition by clique separators. Discret. Math. 55, 221–232 (1985)

    Article  MATH  MathSciNet  Google Scholar 

  34. Tsukiyama S., Ide M., Ariyoshi H., Shirakawa I.: A new algorithm for generating all the maximal independent sets. SIAM J. Comput. 6, 505–517 (1977)

    Article  MATH  MathSciNet  Google Scholar 

  35. Whitesides S.H.: An algorithm for finding clique cut-sets. Inform. Process. Lett. 12, 31–32 (1981)

    Article  MATH  MathSciNet  Google Scholar 

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Correspondence to Vadim V. Lozin.

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This paper extends and unifies some results that earlier appeared in proceedings of the 18th ACM-SIAM Symposium on Discrete Algorithms [26] and 33rd International Symposium on Mathematical Foundations of Computer Science [3]. V. V. Lozin gratefully acknowledges the support of DIMAP—the Centre for Discrete Mathematics and its Applications at the University of Warwick and from EPSRC, grant EP/I01795X/1. M. Milanič supported in part by “Agencija za raziskovalno dejavnost Republike Slovenije”, research program P1–0285 and research projects J1–4010, J1–4021 and N1–0011.

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Lozin, V.V., Milanič, M. & Purcell, C. Graphs Without Large Apples and the Maximum Weight Independent Set Problem. Graphs and Combinatorics 30, 395–410 (2014). https://doi.org/10.1007/s00373-012-1263-y

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