Literal Varieties of Languages Induced by Homomorphisms onto Nilpotent Groups
نویسندگان
چکیده
We present here new hierarchies of literal varieties of languages. Each language under consideration is a disjoint union of a certain collection of “basic” languages described here. Our classes of languages correspond to certain literal varieties of homomorphisms from free monoids onto nilpotent groups of class ≤ 2.
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تاریخ انتشار 2008