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On the Maximal Sum of Exponents of Runsin a String

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Part of the book series: Lecture Notes in Computer Science ((LNTCS,volume 6460))

Abstract

A run is an inclusion maximal occurrence in a string (as a subinterval) of a repetition v with a period p such that 2p ≤ |v|. The exponent of a run is defined as |v|/p and is ≥ 2. We show new bounds on the maximal sum of exponents of runs in a string of length n. Our upper bound of 4.1 n is better than the best previously known proven bound of 5.6 n by Crochemore & Ilie (2008). The lower bound of 2.035 n, obtained using a family of binary words, contradicts the conjecture of Kolpakov & Kucherov (1999) that the maximal sum of exponents of runs in a string of length n is smaller than 2n.

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Crochemore, M., Kubica, M., Radoszewski, J., Rytter, W., Waleń, T. (2011). On the Maximal Sum of Exponents of Runsin a String. In: Iliopoulos, C.S., Smyth, W.F. (eds) Combinatorial Algorithms. IWOCA 2010. Lecture Notes in Computer Science, vol 6460. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-19222-7_2

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  • DOI: https://doi.org/10.1007/978-3-642-19222-7_2

  • Publisher Name: Springer, Berlin, Heidelberg

  • Print ISBN: 978-3-642-19221-0

  • Online ISBN: 978-3-642-19222-7

  • eBook Packages: Computer ScienceComputer Science (R0)

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