Siberian Mathematical Journal

, Volume 48, Issue 5, pp 939–948 | Cite as

Index sets of decidable models

  • E. B. Fokina


We study the index sets of the class of d-decidable structures and of the class of d-decidable countably categorical structures, where d is an arbitrary arithmetical Turing degree. It is proved that the first of them is m-complete ∑ 3 0, d , and the second is m-complete ∑ 3 0, d \∑ 3 0, d in the universal computable numbering of computable structures for the language with one binary predicate.


index set computable structure decidable structure countably categorical theory 


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Copyright information

© Springer Science+Business Media, Inc. 2007

Authors and Affiliations

  1. 1.Sobolev Institute of MathematicsNovosibirskRussia

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