In this paper we introduce a sharpening of the Parikh mapping and investigate its basic properties. The new mapping is based on square matrices of a certain form. The classical Parikh vector appears in such a matrix as the second diagonal. However, the matrix product gives more information about a word than the Parikh vector. We characterize the matrix products and establish also an interesting interconnection between mirror images of words and inverses of matrices.
@article{ITA_2001__35_6_551_0, author = {Mateescu, Alexandru and Salomaa, Arto and Salomaa, Kai and Yu, Sheng}, title = {A sharpening of the Parikh mapping}, journal = {RAIRO - Theoretical Informatics and Applications - Informatique Th\'eorique et Applications}, volume = {35}, year = {2001}, pages = {551-564}, mrnumber = {1922295}, zbl = {1005.68092}, language = {en}, url = {http://dml.mathdoc.fr/item/ITA_2001__35_6_551_0} }
Mateescu, Alexandru; Salomaa, Arto; Salomaa, Kai; Yu, Sheng. A sharpening of the Parikh mapping. RAIRO - Theoretical Informatics and Applications - Informatique Théorique et Applications, Tome 35 (2001) pp. 551-564. http://gdmltest.u-ga.fr/item/ITA_2001__35_6_551_0/
[1] On the injectivity of the Parikh matrix mapping (submitted). | Zbl 0997.68075
, and ,[2] Some decision problems concerning semilinearity and commutation. J. Comput. System Sci. (to appear). | MR 1939772 | Zbl 1059.68061
, , and ,[3] On slender languages. EATCS Bull. 64 (1998) 145-152. | MR 1618305 | Zbl 0898.68042
,[4] On Parikh slender languages and power series. J. Comput. System Sci. 52 (1996) 185-190. | MR 1375813 | Zbl 0846.68056
,[5] An attempt to define mildly context-sensitive languages. Publ. Math. Debrecen 54 (1999) 865-876. | MR 1709927 | Zbl 0981.68086
,[6] A characterization of poly-slender context-free languages. RAIRO: Theoret. Informatics Appl. 34 (2000) 77-86. | Numdam | MR 1771131 | Zbl 0966.68097
, and ,[7] A decidable property of iterated morphisms. Springer, Lecture Notes in Comput. Sci. 104 (1981) 152-158. | Zbl 0457.68095
,[8] On context-free languages. J. Assoc. Comput. Mach. 13 (1966) 570-581. | MR 209093 | Zbl 0154.25801
,[9] Handbook of Formal Languages 1-3. Springer-Verlag, Berlin, Heidelberg, New York (1997). | Zbl 0866.68057
and ,[10] Subwords, edited by M. Lothaire, Combinatorics on Words. Addison-Wesley, Reading, Mass. (1983) 105-142. | MR 675953
and ,[11] Formal Languages. Academic Press, New York (1973). | MR 438755 | Zbl 0262.68025
,