Summary
An infinite word x has finite index if the exponents of the powers of primitive words that are factors of x are bounded. F. Mignosi has proved that a Sturmian word has finite index if and only if the coefficients of the continued fraction development of its slope are bounded. Mignosi’s proof relies on a delicate analysis of the approximation of the slope by rational numbers. We give here a proof based on combinatorial properties of words, and give some additional relations between the exponents and the slope.
This is a preview of subscription content, log in via an institution.
Buying options
Tax calculation will be finalised at checkout
Purchases are for personal use only
Learn about institutional subscriptionsPreview
Unable to display preview. Download preview PDF.
References
J. Berstel, Recent results on Sturmian words, in: J. Dassow, G. Rozenberg, A. Salomaa (eds.) Developments in Language Theory II, World Scientific, 1996.
J. Berstel, P. Séébold, Sturmian Words, in: M. Lothaire (ed.) Algebraic Combinatorics on Words, in preparation.
J. Berstel et P. Séébold, A remark on morphic Sturmian words, Informatique théorique et applications 28 (1994), 255–263.
E. Bombieri, J. E. Taylor, Which distributions of matter diffract? An initial investigation, J. Phys. 47 (1986), Colloque C3, 19–28.
J. E. Bresenham, Algorithm for computer control of a digital plotter, IBM Systems J. 4 (1965), 25–30.
T. C. Brown, A characterization of the quadratic irrationals, Canad. Math. Bull. 34 (1991), 36–41.
D. Crisp, W. Moran, A. Pollington, P. Shiue, Substitution invariant cutting sequences, J. Théorie des Nombres de Bordeaux 5 (1933), 123–137.
E. Coven, G. Hedlund, Sequences with minimal block growth, Math. Systems Theory 7 (1973), 138–153.
A. De Luca, Sturmian words: structure, combinatorics, and their arithmetics, Theoret. Comput. Sci. 183 (1997), 45–82.
A. De Luca, Combinatorics of standard Sturmian words, in: J. Mycielski, G. Rozenberg, A. Salomaa (eds.) Structures in Logic and Computer Science, Lect. Notes Comp. Sci. Vol. 1261, Springer-Verlag, 1997, pp 249–267.
A. De Luca, Standard Sturmian morphisms, Theoret. Comput. Sci. 178 (1997), 205–224.
A. De Luca et F. Mignosi, Some combinatorial properties of Sturmian words, Theoret. Comput. Sci. 136 (1994), 361–385.
S. Dulucq, D. Gouyou-Beauchamps, Sur les facteurs des suites de Sturm, Theoret. Comput. Sci. 71 (1990), 381–400.
A. S. Fraenkel, M. Mushkin, U. Tassa, Determination of ⌊nθ⌋ by its sequence of differences, Canad. Math. Bull. 21h (1978), 441–446.
G.A. Hedlund, Sturmian minimal sets, Amer. J. Math 66 (1944), 605–620.
M. Morse, G.A. Hedlund, Symbolic dynamics, Amer. J. Math 60 (1938), 815–866.
M. Morse, G.A. Hedlund, Sturmian sequences, Amer. J. Math 61 (1940), 1–42.
S. Ito, S. Yasutomi, On continued fractions, substitutions and characteristic sequences, Japan. J. Math. 16 (1990), 287–306.
J. Karhumäki, On strongly cube-free w-words generated by binary morphisms, in FCT’81, pp. 182–189, Lect. Notes Comp. Sci. Vol. 117, Springer-Verlag, 1981.
J. Karhumäki, On cube-free w-words generated by binary morphisms, Discr. Appl. Math. 5 (1983), 279–297.
F. Mignosi, On the number of factors of Sturmian words, Theoret. Comput. Sci. 82 (1991), 71–84.
F. Mignosi et G. Pirillo, Repetitions in the Fibonacci infinite word, Theoret. Inform. Appl. 26,3 (1992), 199–204.
F. Mignosi, R Séébold, Morphismes sturmiens et regies de Rauzy, J. Théorie des Nombres de Bordeaux 5 (1993), 221–233.
M. Queffélec, Substitution Dynamical Systems - Spectral Analysis, Lecture Notes Math., vol. 1294, Springer-Verlag, 1987.
G. Rauzy, Suites à termes dans un alphabet fini, Sémin. Théorie des Nombres (1982–1983), 25–01,25–16, Bordeaux.
G. Rauzy, Mots infinis en arithmétique, in: Automata on infinite words (D. Perrin ed.), Lect. Notes Comp. Sci. 192 (1985), 165–171.
R Séébold, Fibonacci morphisms and Sturmian words, Theoret. Comput. Sci. 88 (1991), 367–384.
C. Series, The geometry of Markoff numbers, The Mathematical Intelligencer 7 (1985), 20–29.
K. B. Stolarsky, Beatty sequences, continued fractions, and certain shift operators, Cand. Math. Bull. 19 (1976), 473–482.
B. A. Venkov, Elementary Number Theory, Wolters-Noordhoff, Groningen, 1970.
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 1999 Springer-Verlag Berlin Heidelberg
About this chapter
Cite this chapter
Berstel, J. (1999). On the Index of Sturmian Words. In: Karhumäki, J., Maurer, H., Păun, G., Rozenberg, G. (eds) Jewels are Forever. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-60207-8_25
Download citation
DOI: https://doi.org/10.1007/978-3-642-60207-8_25
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-642-64304-0
Online ISBN: 978-3-642-60207-8
eBook Packages: Springer Book Archive