Semi-discrete context-free languages †

A language L over a finite alphabet is said to be semi-discrete if there exists a positive integer k such that L contains at most k words of any given length. If k=1, the language is said to be discrete. It is shown that a language is semi-discrete and context-free iff it is a discrete union of languages of the form , iff it is a finite disjoint union of discrete context-free languages. Closure properties and decision problems are studied for the class of semi-discrete context-free languages

[1]  Jorge E. Mezei,et al.  On Relations Defined by Generalized Finite Automata , 1965, IBM J. Res. Dev..

[2]  Huei-Jan Shyr,et al.  H-Bounded and Semi-discrete Languages , 1981, Inf. Control..

[3]  Tom Head,et al.  Hypercodes in Deterministic and Slender 0L Languages , 1980, Inf. Control..

[4]  Seymour Ginsburg,et al.  The mathematical theory of context free languages , 1966 .

[5]  Luc Boasson,et al.  Langages Algebriques, Paires Iterantes et Transductions Rationnelles , 1976, Theor. Comput. Sci..

[6]  Samuel Eilenberg,et al.  Automata, languages, and machines. A , 1974, Pure and applied mathematics.

[7]  Grzegorz Rozenberg,et al.  The Length Sets of D0L Languages are Uniformly Bounded , 1974, Inf. Process. Lett..

[8]  Michel Latteux,et al.  A New Proof of two Theorems about Rational Transductions , 1979, Theor. Comput. Sci..

[9]  Jean Berstel,et al.  Transductions and context-free languages , 1979, Teubner Studienbücher : Informatik.

[10]  Seymour Ginsburg,et al.  On the Periodicity of Word-Length in DOL Languages , 1974, Inf. Control..

[11]  Joffroy Beauquier,et al.  Generateurs Algebriques et Systemes de Paires Iterantes , 1979, Theor. Comput. Sci..

[12]  Seymour Ginsburg,et al.  AFL with the Semilinear Property , 1971, J. Comput. Syst. Sci..