Abstract
A (fractional) repetition in a word w is a subword with the period of at most half of the subword length. We study maximal repetitions occurring in w, that is those for which any extended subword of w has a bigger period. The set of such repetitions represents in a compact way all repetitions in w.
We first study maximal repetitions in Fibonacci words — we count their exact number, and estimate the sum of their exponents. These quantities turn out to be linearly-bounded in the length of the word. We then prove that the maximal number of maximal repetitions in general words (on arbitrary alphabet) of length n is linearly-bounded in n, and we mention some applications and consequences of this result.
Article
The work has been done during the first author’s visit of LORIA/INRIA-Lorraine supported by a grant from the French Ministry of Public Education and Research. The first author has been also in part supported by the Russian Foundation of Fundamental Research, under grant 96-01-01068, and by the Russian Federal Programme “Integration”, under grant 473. The work has been done within a joint project of the French-Russian A.M.Liapunov Institut of Applied Mathematics and Informatics at Moscow University
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Kolpakov, R., Kucherov, G. (1999). On maximal repetitions in words. In: Ciobanu, G., Păun, G. (eds) Fundamentals of Computation Theory. FCT 1999. Lecture Notes in Computer Science, vol 1684. Springer, Berlin, Heidelberg. https://doi.org/10.1007/3-540-48321-7_31
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DOI: https://doi.org/10.1007/3-540-48321-7_31
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