Infinite Words Rich and Almost Rich in Generalized Palindromes

  • Edita Pelantová
  • Štěpán Starosta
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6795)


We focus on Θ-rich and almost Θ-rich words over a finite alphabet \(\mathcal{A}\), where Θ is an involutive antimorphism over \(\mathcal{A}^*\). We show that any recurrent almost Θ-rich word u is an image of a recurrent Θ′-rich word under a suitable morphism, where Θ′ is again an involutive antimorphism. Moreover, if the word u is uniformly recurrent, we show that Θ′ can be set to the reversal mapping. We also treat one special case of almost Θ-rich words. We show that every Θ-standard word with seed is an image of an Arnoux-Rauzy word.


palindrome pseudopalindrome palindromic defect richness 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • Edita Pelantová
    • 1
  • Štěpán Starosta
    • 1
  1. 1.Department of MathematicsFNSPE, Czech Technical University in PraguePraha 2Czech Republic

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