The Number of Occurrences of Letters Versus Their Distribution in Some E0L Languages

Department of Mathematics, Utrecht University, Utrecht-Uithof, The Netherlands
Information and Control 11/1974; 26:256-271. DOI: 10.1016/S0019-9958(74)91379-5
Source: DBLP

ABSTRACT A characterization theorem is given for a class of developmental languages. The theorem binds together the number of occurrences of letters in the words of the given language with the distribution of these letters.

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    ABSTRACT: This paper provides a method of “decomposing” a subclass of ET0L languages into deterministic ET0L languages. This allows one to use every known example of a language which is not a deterministic ET0L language to produce languages which are not ET0L languages.
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    Information and Control 01/1980; 44:134-163.


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