On Language Decompositions and Primality

  • Michael Domaratzki
  • Kai Salomaa
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6570)


Concatenation of strings and languages is a fundamental operation on formal languages. Here we consider the inverse operation of language decomposition, where we want to represent a given language as a non-trivial concatenation of two languages. The associated notions of prime languages and prime decompositions have been originally introduced by Mateescu, A. Salomaa and Yu. We consider also extensions of the decomposability problem with respect to orthogonal concatenation, as well as, more general operations defined by sets of trajectories.


Regular Language Prime Language Prime Decomposition Decomposition Problem Input Word 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2011

Authors and Affiliations

  • Michael Domaratzki
    • 1
  • Kai Salomaa
    • 2
  1. 1.Department of Computer ScienceUniversity of ManitobaWinnipegCanada
  2. 2.School of ComputingQueen’s UniversityKingstonCanada

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