Block Palindromes: A New Generalization of Palindromes

  • Keisuke GotoEmail author
  • I Tomohiro
  • Hideo Bannai
  • Shunsuke Inenaga
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11147)


We study a new generalization of palindromes and gapped palindromes called block palindromes. A block palindrome is a string that becomes a palindrome when identical substrings are replaced with a distinct character. We investigate several properties of block palindromes and in particular, study substrings of a string which are block palindromes. In so doing, we introduce the notion of a maximal block palindrome, which leads to a compact representation of all block palindromes that occur in a string. We also propose an algorithm which enumerates all maximal block palindromes that appear in a given string \(T\) in \(O(|T| + \Vert MBP (T)\Vert )\) time, where \(\Vert MBP (T)\Vert \) is the output size, which is optimal unless all the maximal block palindromes can be represented in a more compact way.


Palindrome Enumeration algorithm Factorization 


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Copyright information

© Springer Nature Switzerland AG 2018

Authors and Affiliations

  • Keisuke Goto
    • 1
    Email author
  • I Tomohiro
    • 2
  • Hideo Bannai
    • 3
  • Shunsuke Inenaga
    • 3
  1. 1.Fujitsu Laboratories Ltd.KawasakiJapan
  2. 2.Kyushu Institute of TechnologyIizukaJapan
  3. 3.Kyushu UniversityFukuokaJapan

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