منابع مشابه
Groups and NTS Languages
The context-free groups are known to be exactly the tinitely generated virtually free groups [ 19, 111. We give here a new combinatorial property which characterizes these groups: they are “locally primary.” A corollary of this property is that the cylinder generated by the group languages is included in the family of NTS languages. In particular, every context-free group language is NTS.
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ژورنال
عنوان ژورنال: Transactions of the American Mathematical Society
سال: 1983
ISSN: 0002-9947
DOI: 10.1090/s0002-9947-1983-0704619-4