Abstract
In this paper, we study the following problem: Which characteristics does a codeC possess when the syntactic monoidsyn(C *) of the star closureC * ofC is a group? For a codeC, if the syntactic monoidsyn(C *) is a group, then we callC a group code. This definition of a group code is different from the one in [1] (see [1], 46–47). Schützenberger had characterized the structure of finite group codes and had proved thatC is a finite group code if and only ifC is a full uniform code (see [5], [8]). Fork-prefix andk-suffix codes withk≥2,k-infix,k-outfix,p-infix,s-infix, right semaphore codes and left semaphore codes, etc., we obtain similar results. It is proved that the above mentioned codes are group codes if and only if they are uniform codes.
Similar content being viewed by others
References
Berstel, J., D. Perrin,Theory of Codes, Academic Press, New York 1985.
Dongyang, Long,k-Outfix Codes, Chinese Annals of Math., Vol. 10, Ser. A (1989), 94–99 (in Chinese).
Dongyang, Long,k-Prefix Codes and k-Infix Codes, Acta Mathematical Sinica, Vol. 33 (1990), 414–421 (in Chinese).
Ito, M., H. Jurgensen, H. J. Shyr, G. Theirrin,Outfix and Infix Codes and Related Classes of Languages, J. Comput. Systems Sci., to appear.
Lallement, G.,Semigroups and Combinatorial Applications, John Wiley & Son, New York, 1979.
Reis, C. M., G. Therrin,Reflective Star Languages and Codes, Information and Control42 (1979), 1–9.
Shyr, H. J.,Free Monoids and Languages, Soochow University Taipei, Taiwan, 1979.
Schützenberger, M. P.,Une théorie algèbrigue du codage, C. R. Acad. Sci. Paris242, 862–864, Séminaire Dubriel-pisot, 1955–1956, No. 15, 1956.
Salomaa, A.,Jewels of Formal Language Theory, Computer Sci. Press, 1981.
Author information
Authors and Affiliations
Additional information
Communicated by B. M. Schein
The author would like to thank the referee who helped the author with revising the paper. Thanks are also due to Prof. Boris M. Schein for his valuable suggestions and kind help.
Rights and permissions
About this article
Cite this article
Long, D. On the structure of some group codes. Semigroup Forum 45, 38–44 (1992). https://doi.org/10.1007/BF03025747
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF03025747