Rich and Periodic-Like Words

  • Michelangelo Bucci
  • Aldo de Luca
  • Alessandro De Luca
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5583)


In this paper we investigate the periodic structure of rich words (i.e., words having the highest possible number of palindromic factors), giving new results relating them with periodic-like words. In particular, some new characterizations of rich words and rich palindromes are given. We also prove that a periodic-like word is rich if and only if the square of its fractional root is also rich.


Median Factor Empty Word Fractional Root Complete Return Binary Alphabet 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2009

Authors and Affiliations

  • Michelangelo Bucci
    • 1
  • Aldo de Luca
    • 1
  • Alessandro De Luca
    • 1
  1. 1.Dipartimento di Matematica e Applicazioni “R. Caccioppoli”Università degli Studi di Napoli Federico IINapoliItaly

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