Abstract
Duplication is an operation generating a language from a single word by iterated application of rewriting rules u →uu on factors. We extend this operation to entire languages and investigate, whether the classes of the Chomsky hierarchy are closed under duplication. Here we treat mainly bounded duplication, where the factors duplicated cannot exceed a given length.
While over two letters the regular languages are closed under bounded duplication, over three or more letters they are not, if the length bound is 4 or greater. For 2 they are closed under duplication, the case of 3 remains open. Finally, the class of context-free languages is closed under duplication over alphabets of any size.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
References
Book, R., Otto, F.: String-Rewriting Systems. Springer, Berlin (1988)
Currie, J.D.: There are Ternary Circular Square-free Words of Length n for n ≥ 18. Electric Journal of Combinatorics 9(1), N10 (2002)
Dassow, J., Mitrana, V., Păun, G.: On the Regularity of Duplication Closure. Bull. EATCS 69, 133–136 (1999)
Harrison, M.A.: Introduction to Formal Language Theory. Reading, Mass. (1978)
Leupold, P.: n-Bounded Duplication Codes. In: Proceedings of the ICALP-Workshop on Words, Avoidability, Complexity, Turku 2004. Technical Report 2004-07, Laboratoire de Recherche en Informatique d’Amiens, Amiens (2004)
Leupold, P., Martín Vide, C., Mitrana, V.: Uniformly Bounded Duplication Languages. Discrete Applied Mathematics 146(3), 301–310 (2005)
Leupold, P., Mitrana, V.: Uniformly Bounded Duplication Codes (submitted)
Leupold, P., Mitrana, V., Sempere, J.: Languages Arising from Gene Repeated Duplication. In: Jonoska, N., Păun, G., Rozenberg, G. (eds.) Aspects of Molecular Computing. LNCS, vol. 2950, pp. 297–308. Springer, Heidelberg (2003)
Martín-Vide, C., Păun, G.: Duplication Grammars. Acta Cybernetica 14, 101–113 (1999)
Mitrana, V., Rozenberg, G.: Some Properties of Duplication Grammars. Acta Cybernetica 14, 165–177 (1999)
Salomaa, A.: Formal Languages. Academic Press, Orlando (1973)
Wang, M.-W.: On the Irregularity of the Duplication Closure. Bull. EATCS 70, 162–163 (2000)
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2006 Springer-Verlag Berlin Heidelberg
About this paper
Cite this paper
Ito, M., Leupold, P., Shikishima-Tsuji, K. (2006). Closure of Language Classes Under Bounded Duplication. In: Ibarra, O.H., Dang, Z. (eds) Developments in Language Theory. DLT 2006. Lecture Notes in Computer Science, vol 4036. Springer, Berlin, Heidelberg. https://doi.org/10.1007/11779148_22
Download citation
DOI: https://doi.org/10.1007/11779148_22
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-540-35428-4
Online ISBN: 978-3-540-35430-7
eBook Packages: Computer ScienceComputer Science (R0)