Homomorphic images of sentential form languages defined by semi-Thue systems
نویسندگان
چکیده
منابع مشابه
Homomorphic Images of Sentential Form Languages Defined by Semi-Thue Systems
We investigate various language famili$:s which can be obtained from sentential form languages of semi-Thue systems by applying codmgs, weak codings, non-erasing homomorphisms, and arbitrary homomorphi5rns. We also distinguish between monotone, contexi-independent, and context-dependent semi-Thur systems with at most one or finitely many starting words. Finally, we study the effect of erasing p...
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ژورنال
عنوان ژورنال: Theoretical Computer Science
سال: 1984
ISSN: 0304-3975
DOI: 10.1016/0304-3975(84)90101-4