Decidable Expansions of Labelled Linear Orderings
نویسندگان
چکیده
Let M = (A,<, P ) where (A,<) is a linear ordering and P denotes a finite sequence of monadic predicates on A. We show that if A contains an interval of order type ω or −ω, and the monadic second-order theory of M is decidable, then there exists a non-trivial expansion M ′ of M by a monadic predicate such that the monadic second-order theory of M ′ is still decidable.
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تاریخ انتشار 2010