Showing papers by "Grzegorz Rozenberg published in 1976"
TL;DR: This paper provides a method of “decomposing” a subclass of ET0L languages into deterministic ET1L languages, which allows one to use every known example of a language which is not a deterministicET0L language to produce languages which are not ET0l languages.
33 citations
TL;DR: The main result binds together the number of occurrences (in words of a given ETOL language) of letters, from a given set, with their distribution and provides a very helpful tool to prove that certain languages are not ETOL.
Abstract: In this paper a partial characterization for a subclass of ETOL languages is obtained. The main result binds together the number of occurrences (in words of a given ETOL language) of letters, from a given set, with their distribution. It provides a very helpful tool to prove that certain languages are not ETOL.
14 citations
TL;DR: In the context independent L systems with varlsus generalizations of context free grammars, the class of ETOL systems (see [S ] ) fGgnls is perhaps the central cl;dss among various classes of context indepenGent L systems.
7 citations
TL;DR: Variations of programmed grammars, where control is imposed over sets of productions rather than over single productions, are studied, which corresponds to the notion of tables in the theory of L systems.
6 citations
01 Jan 1976
TL;DR: It is proved that these two generalizations of the notion of a random context grammar do not increase the language generating power of the class of random context grammars.
Abstract: Two generalizations of the notion of a random context grammar are considered. The first one equips a random context grammar with a possibility of a (limited) counting of a number of occurrences of the symbol to be rewritten. The second one applies productions in parallel (as in L systems). It is proved that these two generalizations do not increase the language generating power of the class of random context grammars. Also some normal form theorems are proved.
6 citations
5 citations
06 Sep 1976
TL;DR: The characterization of the class of ETOL languages, and its main subclasses (EOL, EDTOL, EDOL) in terms of various subclasses of theclass of context-free programmed grammars is provided.
Abstract: The relationship between ETOL systems and context-free programmed grammars is investigated. The characterization of the class of ETOL languages, and its main subclasses (EOL, EDTOL, EDOL) in terms of various subclasses of the class of context-free programmed grammars is provided. Then an extension of the notion of an ETOL system is investigated. In this way a characterization of the class of context-free programmed languages is provided.
3 citations
2 citations