Decidability and undecidability of extensions of second (first) order theory of (generalized) successor
Autor: | Calvin C. Elgot, Michael O. Rabin |
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Rok vydání: | 1966 |
Předmět: | |
Zdroj: | Journal of Symbolic Logic. 31:169-181 |
ISSN: | 1943-5886 0022-4812 |
DOI: | 10.2307/2269808 |
Popis: | We study certain first and second order theories which are semantically defined as the sets of all sentences true in certain given structures. Let be a structure where A is a non-empty set, λ is an ordinal, and Pα is an n(α)-ary relation or function4 on A. With we associate a language L appropriate for which may be a first or higher order calculus. L has an n(α)-place predicate or function constant P for each α < λ. We shall study three types of languages: (1) first-order calculi with equality; (2) second-order monadic calculi which contain monadic predicate (set) variables ranging over subsets of A; (3) restricted (weak) second-order calculi which contain monadic predicate variables ranging over finite subsets of A. |
Databáze: | OpenAIRE |
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