A Horn Clause that Implies and Undecidable Set of Horn Clauses
نویسنده
چکیده
In this paper we prove that there exists a Horn clause H such that the problem: given a Horn clause G. Is G a consequence of H ? is not recursive. Equivalently, there exists a one-clause PROLOG program such that there is no PROLOG implementation answering TRUE if the program implies a given goal and FALSE otherwise. We give a short survey of earlier results concerning clause implication and prove a classical Linial-Post theorem as a consequence of one of them.
منابع مشابه
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