Pseudo-inversion on formal languages

Da Jung Cho, Yo Sub Han, Shin Dong Kang, Hwee Kim, Sang Ki Ko, Kai Salomaa

Research output: Chapter in Book/Report/Conference proceedingConference contribution

6 Citations (Scopus)


We consider the pseudo-inversion operation inspired by a biological event as a result of the partial inversion. We define the pseudo-inversion of a string w=uxv to consist of all strings vRxuR, where uv ≠ λ and consider the operation from a formal language theoretic viewpoint. We show that regular languages are closed under the pseudo-inversion operation whereas context-free languages are not. Furthermore, we consider the iterated pseudo-inversion operation and establish the basic properties. Finally, we introduce the pseudo-inversion-freeness and examine closure properties and decidability problems for regular and context-free languages. We establish that pseudo-inversion-freeness is decidable in polynomial time for regular languages and undecidable for context-free languages.

Original languageEnglish
Title of host publicationUnconventional Computation and Natural Computation - 13th International Conference, UCNC 2014, Proceedings
PublisherSpringer Verlag
Number of pages12
ISBN (Print)9783319081229
Publication statusPublished - 2014
Event13th International Conference on Unconventional Computation and Natural Computation, UCNC 2014 - London, ON, Canada
Duration: 2014 Jul 142014 Jul 18

Publication series

NameLecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)
Volume8553 LNCS
ISSN (Print)0302-9743
ISSN (Electronic)1611-3349


Other13th International Conference on Unconventional Computation and Natural Computation, UCNC 2014
CityLondon, ON

All Science Journal Classification (ASJC) codes

  • Theoretical Computer Science
  • Computer Science(all)


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