×

Farey boat: continued fractions and triangulations, modular group and polygon dissections. (English) Zbl 1437.11097

In this article the authors introduce an interesting combinatorial interpretation of several known results on continued fractions. In particular they consider two theorems relating continued fractions and triangulations studied by J. H. Conway and H. S. M. Coxeter [Math. Gaz. 57, 87–94 (1973; Zbl 0285.05028)], and C. Series [J. Lond. Math. Soc. (2) 31, 69–80 (1985; Zbl 0545.30001)]. The authors have obtained more general polygon dissections when extending these theorems for elements of the modular group \(\mathrm{PSL}(2,\mathbb Z)\). These polygon dissections are interpreted as walks in the Farey tessellation. The combinatorial model of continued fractions can be further developed to obtain a canonical presentation of elements of \(\mathrm{PSL}(2,\mathbb Z)\).

MSC:

11J70 Continued fractions and generalizations
11A55 Continued fractions
11-03 History of number theory

References:

[1] Adamczewski, B., Allouche, J.-P.: Reversals and palindromes in continued fractions. Theor. Comput. Sci. 380, 220-237 (2007) · Zbl 1118.68110 · doi:10.1016/j.tcs.2007.03.017
[2] Aigner, M.: Markov’s Theorem and 100 Years of the Uniqueness Conjecture. A Mathematical Journey from Irrational Numbers to Perfect Matchings. Springer, Cham (2013) · Zbl 1276.00006
[3] Bergeron, F., Reutenauer, C.: SLk \(SL_k\)-tilings of the plane. Ill. J. Math. 54, 263-300 (2010) · Zbl 1236.13018 · doi:10.1215/ijm/1299679749
[4] Berstel, J., Reutenauer, C.: Noncommutative Rational Series with Applications. Encyclopedia of Mathematics and Its Applications, vol. 137. Cambridge University Press, Cambridge (2011) · Zbl 1250.68007
[5] Boca, F.: Products of matrices [1101] and [1011] and the distribution of reduced quadratic irrationals. J. Reine Angew. Math. 606, 149-165 (2007) · Zbl 1135.11050
[6] Borwein, J., van der Poorten, A., Shallit, J., Zudilin, W.: Neverending Fractions. An Introduction to Continued Fractions. Australian Mathematical Society Lecture Series, vol. 23. Cambridge University Press, Cambridge (2014) · Zbl 1307.11001 · doi:10.1017/CBO9780511902659
[7] Bourgain, J., Kontorovich, A.: Beyond Expansion III: Reciprocal Geodesics. arXiv:1610.07260 · Zbl 1403.11054
[8] Caldero, P., Chapoton, F.: Cluster algebras as Hall algebras of quiver representations. Comment. Math. Helv. 81, 595-616 (2006) · Zbl 1119.16013 · doi:10.4171/CMH/65
[9] Conley, C., Ovsienko, V.: Rotundus: triangulations, Chebyshev polynomials, and Pfaffians. Math. Intell. 40, 45-50 (2018) · Zbl 1405.15010 · doi:10.1007/s00283-017-9753-7
[10] Conley, C., Ovsienko, V.: Lagrangian configurations and symplectic cross-ratios. arXiv:1812.04271 · Zbl 1429.53097
[11] Conway, J.H., Coxeter, H.S.M.: Triangulated polygons and frieze patterns. Math. Gaz. 57, 87-94 (1973), 175-183 · Zbl 0285.05028 · doi:10.1017/S0025557200132000
[12] Coxeter, H.S.M.: Frieze patterns. Acta Arith. 18, 297-310 (1971) · Zbl 0217.18101 · doi:10.4064/aa-18-1-297-310
[13] Duke, W., Imamoglu, Ö., Tóth, Á.: Kronecker’s first limit formula, revisited. Res. Math. Sci. 5, 20 (2018) · Zbl 1441.11085 · doi:10.1007/s40687-018-0138-0
[14] Fomin, S., Zelevinsky, A.: Cluster algebras. I. Foundations. J. Am. Math. Soc. 15, 497-529 (2002) · Zbl 1021.16017 · doi:10.1090/S0894-0347-01-00385-X
[15] Fomin, S., Zelevinsky, A.: Cluster algebras. II. Finite type classification. Invent. Math. 154, 63-121 (2003) · Zbl 1054.17024 · doi:10.1007/s00222-003-0302-y
[16] Gekhtman, M., Shapiro, M., Vainshtein, A.: Cluster Algebras and Poisson Geometry. Mathematical Surveys and Monographs, vol. 167. American Mathematical Society, Providence (2010) · Zbl 1217.13001
[17] Graham, R., Knuth, D., Patashnik, O.: Concrete Mathematics. a Foundation for Computer Science Addison-Wesley Publishing Company, Advanced Book Program, Reading (1989). xiv+625 pp. · Zbl 0668.00003 · doi:10.1063/1.4822863
[18] Hall, R., Shiu, P.: The index of a Farey sequence. Mich. Math. J. 51, 209-223 (2003) · Zbl 1038.11062 · doi:10.1307/mmj/1049832901
[19] Hardy, G.H., Wright, E.M.: An Introduction to the Theory of Numbers, sixth edn. Oxford University Press, Oxford (2008). Revised by D.R. Heath-Brown, J.H. Silverman. With a foreword by Andrew Wiles, 621 pp. · Zbl 1159.11001
[20] Henry, C.-S.: Coxeter friezes and triangulations of polygons. Am. Math. Mon. 120, 553-558 (2013) · Zbl 1279.11015 · doi:10.4169/amer.math.monthly.120.06.553
[21] Hirzebruch, F.E.P.: Hilbert modular surfaces. Enseign. Math. (2) 19, 183-281 (1973) · Zbl 0285.14007
[22] Hirzebruch, F.; Zagier, D., Classification of Hilbert modular surfaces, 43-77 (1977), Tokyo · Zbl 0354.14011 · doi:10.1017/CBO9780511569197.005
[23] Karpenkov, O.: Geometry of Continued Fractions. Algorithms and Computation in Mathematics, vol. 26. Springer, Heidelberg, New York, Dordrecht, London (2013) · Zbl 1297.11002
[24] Katok, S.: Coding of closed geodesics after Gauss and Morse. Geom. Dedic. 63(2), 123-145 (1996) · Zbl 0884.20030 · doi:10.1007/BF00148213
[25] McMullen, C.: Uniformly Diophantine numbers in a fixed real quadratic field. Compos. Math. 145, 827-844 (2009) · Zbl 1176.11032 · doi:10.1112/S0010437X09004102
[26] Morier-Genoud, S.: Coxeter’s frieze patterns at the crossroads of algebra, geometry and combinatorics. Bull. Lond. Math. Soc. 47, 895-938 (2015) · Zbl 1330.05035 · doi:10.1112/blms/bdv070
[27] Morier-Genoud, S., Ovsienko, V.: Farey boat II. ℚ-deformations: q \(q\)-deformed rationals and q \(q\)-continued fractions. arXiv:1812.00170 · Zbl 1364.05020
[28] Morier-Genoud, S., Ovsienko, V., Tabachnikov, S.: SL2(Z)\( \text{SL}_2(\mathbb{Z})\)-tilings of the torus, Coxeter-Conway friezes and Farey triangulations. Enseign. Math. 61, 71-92 (2015) · Zbl 1331.05022 · doi:10.4171/LEM/61-1/2-4
[29] Morier-Genoud, S., Ovsienko, V., Schwartz, R., Tabachnikov, S.: Linear difference equations, frieze patterns and combinatorial Gale transform. Forum Math. Sigma, 2, e22 (2014) · Zbl 1297.39004 · doi:10.1017/fms.2014.20
[30] Ovsienko, V.: Partitions of unity in SL(2,Z)\( \text{SL}(2,\mathbb{Z})\), negative continued fractions, and dissections of polygons. Res. Math. Sci. 5(2), 21 (2018) · Zbl 1418.05047 · doi:10.1007/s40687-018-0139-z
[31] Poorten, A. J., An introduction to continued fractions, Kensington, 1985, Cambridge · Zbl 0596.10008 · doi:10.1017/CBO9780511721304.007
[32] Series, C.: The modular surface and continued fractions. J. Lond. Math. Soc. (2) 31(1), 69-80 (1985) · Zbl 0545.30001 · doi:10.1112/jlms/s2-31.1.69
[33] Ustinov, A.: A short proof of Euler’s identity for continuants. Math. Notes 79, 146-147 (2006) · Zbl 1138.33305 · doi:10.1007/s11006-006-0017-7
[34] Zagier, D.: Nombres de classes et fractions continues. Astérisque, 24-25, 81-97 (1975). Journées Arithmétiques de Bordeaux, Conference, Univ. Bordeaux, 1974 · Zbl 0309.12002
This reference list is based on information provided by the publisher or from digital mathematics libraries. Its items are heuristically matched to zbMATH identifiers and may contain data conversion errors. In some cases that data have been complemented/enhanced by data from zbMATH Open. This attempts to reflect the references listed in the original paper as accurately as possible without claiming completeness or a perfect matching.