Abstract.
This article is devoted to simultaneous approximation to ξ and ξ2 by rational numbers with the same denominator, where ξ is an irrational non-quadratic real number. We focus on an exponent β0(ξ) that measures the regularity of the sequence of all exceptionally precise such approximants. We prove that β0(ξ) takes the same set of values as a combinatorial quantity that measures the abundance of palindromic prefixes in an infinite word w. This allows us to give a precise exposition of Roy’s palindromic prefix method. The main tools we use are Davenport-Schmidt’s sequence of minimal points and Roy’s bracket operation.
Similar content being viewed by others
References
J-P Allouche JL Davison M Queffélec LQ Zamboni (2001) ArticleTitleTranscendence of Sturmian or morphic continued fractions J Number Theory 91 39–66 Occurrence Handle0998.11036 Occurrence Handle10.1006/jnth.2001.2669 Occurrence Handle1869317
Y Bugeaud (2004) Approximation by Algebraic Numbers Univ Press Cambridge Occurrence Handle1055.11002
Y Bugeaud M Laurent (2005) ArticleTitleExponents of diophantine approximation and Sturmian continued fractions Ann Inst Fourier (Grenoble) 55 773–804 Occurrence Handle02171525 Occurrence Handle2149403
J Cassaigne (1999) ArticleTitleLimit values of the recurrence quotient of Sturmian sequences Theoret Comput Sci 218 3–12 Occurrence Handle0916.68115 Occurrence Handle10.1016/S0304-3975(98)00247-3 Occurrence Handle1687748
H Davenport W Schmidt (1967) ArticleTitleApproximation to real numbers by quadratic irrationals Acta Arith 13 169–176 Occurrence Handle0155.09503 Occurrence Handle219476
H Davenport W Schmidt (1969) ArticleTitleApproximation to real numbers by algebraic integers Acta Arith 15 393–416 Occurrence Handle0186.08603 Occurrence Handle246822
S Fischler (2006) ArticleTitlePalindromic prefixes and episturmian words J Comb Theory Series A 113 1281–1304 Occurrence Handle05078215 Occurrence Handle10.1016/j.jcta.2005.12.001 Occurrence Handle2259061
S Fischler (2004) ArticleTitleSpectres pour l’approximation d’un nombre réel et de son carré C R Acad Sci Paris Ser I 339 679–682 Occurrence Handle1073.11048 Occurrence Handle2110935
V Jarník (1938) ArticleTitleZum Khintchineschen Übertragungssatz Trudy Tbilisskogo Math Inst im A M Razmadze 3 193–212
Roy D (2004) On two exponents of approximation related to a real number and its square. Canad J Math, to appear; preprint math NT/0409232
D Roy (2003) ArticleTitleApproximation simultanée d’un nombre et de son carré CR Acad Sci Paris Ser I 336 1–6 Occurrence Handle1038.11042
D Roy (2004) ArticleTitleApproximation to real numbers by cubic algebraic integers I Proc London Math Soc 88 42–62 Occurrence Handle1035.11028 Occurrence Handle10.1112/S002461150301428X Occurrence Handle2018957
Schmidt W (1980) Diophantine Approximation. Lect Notes Math 785. Berlin Heidelberg New York: Springer
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Fischler, S. Palindromic Prefixes and Diophantine Approximation. Mh Math 151, 11–37 (2007). https://doi.org/10.1007/s00605-006-0425-5
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00605-006-0425-5