Abstract
A hole is an induced cycle with at least four vertices. A hole is even if it has an even number of vertices. Even-hole-free graphs are being actively studied in the literature. It is not known whether even-hole-free graphs can be optimally colored in polynomial time. A diamond is the graph obtained from the clique of four vertices by removing one edge. A kite is a graph consists of a diamond and another vertex adjacent to a vertex of degree two in the diamond. Kloks et al. (J Combin Theory B 99:733–800, 2009) designed a polynomial-time algorithm to color an (even hole, diamond)-free graph. In this paper, we consider the class of (even hole, kite)-free graphs which generalizes (even hole, diamond)-free graphs. We prove that a connected (even hole, kite)-free graph is diamond-free, or the join of a clique and a diamond-free graph, or contains a clique cutset. This result, together with the result of Kloks et al., imply the existence of a polynomial time algorithm to color (even hole, kite)-free graphs. We also prove (even hole, kite)-free graphs are \(\beta \)-perfect in the sense of Markossian, Gasparian and Reed. Finally, we establish the Vizing bound for (even hole, kite)-free graphs.
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References
Addario-Berry, L., Chudnovsky, M., Havet, F., Reed, B., Seymour, P.: Bisimplicial vertices in even-hole-free graphs. J. Comb. Theory Ser. B 98, 1119–1164 (2008)
Barnier, N., Brisset, P.: Graph coloring for air traffic flow management. Ann. Oper. Res. 130, 163–178 (2004)
Berge, C., Chvátal, V. (eds.): Topics on Perfect Graphs. North-Holland, Amsterdam (1984)
Cameron, K., Chaplick, S., Hoàng, C.T.: On the structure of (pan, even hole)-free graphs. August 12 (2015). arXiv:1508.03062
Chang, H.-C., Lu, H.I.: A faster algorithm to recognize even-hole-free graphs. In: Proceedings of the Twenty-Third Annual ACM-SIAM Symposium on Discrete Algorithms , pp. 1286–1297 (2012)
Chudnovsky, M., Kawarabayashi, K., Seymour, P.: Detecting even holes. J. Graph Theory 48, 85–111 (2005)
Conforti, M., Cornuéjols, G., Kapoor, A., Vušković, K.: Even-hole-free graphs, part I: decomposition theorem. J. Graph Theory 39, 6–49 (2002)
Conforti, M., Cornuéjols, G., Kapoor, A., Vušković, K.: Even-hole-free graphs, part II: recognition algorithm. J. Graph Theory 40, 238–266 (2002)
de Figueiredo, C.M.H., Vušković, K.: A class of \(\beta \) perfect graphs. Discrete Math. 216, 169–193 (2000)
Eisenblätter, A., Grötschel, M., Koster, A.M.C.A.: Frequency planning and ramifications of coloring. Discuss. Math. Graph Theory 22, 51–88 (2002)
Golumbic, M.C.: Algorithmic Graph Theory and Perfect Graphs. Academic Press, New York (1980)
Huang, S., da Silva, M.V.G.: A note on coloring (even-hole, cap)-free graphs October 30 (2015). arXiv:1510.09192
Kloks, T., Mülcer, 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)
Markossian, S.E., Gasparian, G.S., Reed, B.A.: \(\beta \)-Perfect graphs. J. Combin. Theory Ser. B 67, 1–11 (1996)
Marx, D.: Graph Coloring problems and their applications in scheduling. Period. Polytech. Electr. Eng. 48, 11–16 (2004)
Narayanan, L.: Channel assignment and graph multicoloring. In: Stojmenović, I. (ed.) Handbook of wireless networks and mobile computing, pp. 71–94. Wiley (2002). ISBN 9780471419020
Tarjan, R.E.: Decomposition by clique separators. Discrete Math. 55, 221–232 (1985)
Vizing, V.G.: On an estimate of the chromatic class of p-graphs. Diskretn. Anal. 3, 25–30 (1964). (in Russian)
Whitesides, S. H.: A method for solving certain graph recognition and optimization problems, with applications to perfect graphs, in [3]
Acknowledgements
This work was supported by the Canadian Tri-Council Research Support Fund. The authors A.M.H. and C.T.H. were each supported by individual NSERC Discovery Grants. Author D.J.F. was supported by an NSERC Undergraduate Student Research Award (USRA).
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Fraser, D.J., Hamel, A.M. & Hoàng, C.T. On the Structure of (Even Hole, Kite)-Free Graphs. Graphs and Combinatorics 34, 989–999 (2018). https://doi.org/10.1007/s00373-018-1925-5
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DOI: https://doi.org/10.1007/s00373-018-1925-5