A predicative and decidable characterization of the polynomial classes of languages
نویسندگان
چکیده
The deenition of a class C of functions is predicative if it doesn't use a class containing C; and is decidable if membershipto C can be decided syntactically, from the construction of its elements. Decidable and predicative characterizations of Poly-time functions are known. We present here such a characterization for the following classes of languages: P, p n ; p n , PH and PSPACE. It is obtained by means of a progressive sequence of restrictions to recursion in a dialect of Lisp.
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ورودعنوان ژورنال:
- Theor. Comput. Sci.
دوره 250 شماره
صفحات -
تاریخ انتشار 2001