The Stable Models of a Predicate Logic Program
نویسندگان
چکیده
Gelfond-Lifschitz [7] introduced the concept of a stable model M of a Predicate Logic Program P . Here we show that, up to a recursive 1-1 coding, the set of all stable models of finite Predicate Logic Programs and the Π1 classes (equivalently, the set of all infinite branches of recursive trees) coincide (Theorems 4.1 and 5.1). Typical consequences: 1) there are finite Predicate Logic Programs which have stable models, but which have no hyperarithmetic stable models; 2) for every recur-
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