PC grammar systems with five context-free components generate all recursively enumerable languages
نویسندگان
چکیده
منابع مشابه
Controlled Pure Grammar Systems
This paper discusses grammar systems that have only terminals, work in the leftmost way, and generate their languages under the regulation by control languages over rule labels. It establishes three results concerning their generative power. First, without any control languages, these systems are not even able to generate all context-free languages. Second, with regular control languages, these...
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Improving the previously known best bound, we show that any recursively enumerable language can be generated with a non-returning parallel communicating (PC) grammar system having six contextfree components. We also present a non-returning universal PC grammar system generating unary languages, that is, a system where not only the number of components, but also the number of productions and the...
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ورودعنوان ژورنال:
- Theor. Comput. Sci.
دوره 299 شماره
صفحات -
تاریخ انتشار 2003