A Series of Run-Rich Strings

  • Wataru Matsubara
  • Kazuhiko Kusano
  • Hideo Bannai
  • Ayumi Shinohara
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5457)


We present a new series of run-rich strings, and give a new lower bound 0.94457567 of the maximum number of runs in a string. We also introduce the general conjecture about a asymptotic behavior of the numbers of runs in the strings defined by any recurrence formula, and show the lower bound can be improved further to 0.94457571235.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2009

Authors and Affiliations

  • Wataru Matsubara
    • 1
  • Kazuhiko Kusano
    • 1
  • Hideo Bannai
    • 2
  • Ayumi Shinohara
    • 1
  1. 1.Graduate School of Information ScienceTohoku UniversitySendaiJapan
  2. 2.Department of InformaticsKyushu UniversityFukuokaJapan

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