Abstract
In this paper, we prove that any two triangulations G and \(G'\) on the sphere with exactly two odd degree vertices can be transformed into each other by two local transformations, called an N-flip and a \(P_2\)-flip, preserving the parity of degree of each vertex, if \(|V(G)|=|V(G')|\). This is an analogy of the same result for triangulations with each vertex even degree [7], but we prove such a fact does not hold for triangulations with at least four odd degree vertices.
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References
Appel, K., Haken, W.: Solution of the four color map problem. Sci. Am. 237, 108–121 (1977)
DeVos, M., Seymour, P.D.: Extending partial \(3\)-colourings in a planar graph. J. Comb. Theory Ser. B 88, 219–225 (2005)
Fisk, S.: The nonexistence of colorings. J. Comb. Theory Ser. B 24, 247–248 (1978)
Higuchi, Y., Nakamoto, A., Ota, K., Sakuma, T.: N-flips in even triangulations on the torus and Dehn twists preserving monodromies. Discrete Math. 311, 1128–1135 (2011)
Kawarabayashi, K., Nakamoto, A., Suzuki, Y.: N-flips in even triangulations on the surfaces. J. Comb. Theory Ser. B 99, 229–246 (2009)
Kawasaki, Y., Matsumoto, N., Nakamoto, A.: N-flips in 4-connected even triangulations on the sphere. Graphs Comb. 31, 1889–1904 (2015)
Nakamoto, A., Sakuma, T., Suzuki, Y.: N-flips in even triangulations on the sphere. J. Graph Theory 51, 260–268 (2006)
Nakamoto, A., Suzuki, Y.: N-flips in even triangulations on the projective plane. Discrete Math. 308, 5454–5462 (2008)
Negami, S.: Diagonal flips in triangulations of surfaces. Discrete Math. 135, 225–232 (1994)
Negami, S.: Diagonal flips of triangulations on surfaces, a survey. Yokohama Math. J. 47, 1–40 (1999)
Suzuki, Y., Watanabe, T.: Generating even triangulations of the projective plane. J. Graph Theory 56, 333–349 (2007)
Tsai, M.T., West, D.B.: A new proof of 3-colorability of Eulerian triangulations. Ars Math. Contemp. 4, 73–77 (2011)
Wagner, K.: Bemerkungen zum Vierfarbenproblem. J. der Deut. Math. 46, 26–32 (1936)
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Asayama, Y., Matsukawa, R., Matsumoto, N. et al. N-Flips in Triangulations with Two Odd Degree Vertices. Graphs and Combinatorics 36, 469–490 (2020). https://doi.org/10.1007/s00373-019-02130-2
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DOI: https://doi.org/10.1007/s00373-019-02130-2