On a classification of context-free languages
نویسنده
چکیده
The set E of strings is said to be definable (strongly definable) if there is a context-free grammar G such that E is the set of all terminal strings generated from the initial symbol (from all non terminal symbols) of G. The classification of definable and strongly definable sets in dependence on minimal number of nonterminal symbols needed for their generation is given.
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ورودعنوان ژورنال:
- Kybernetika
دوره 3 شماره
صفحات -
تاریخ انتشار 1967