Abstract
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 ∑ 0, d3 , and the second is m-complete ∑ 0, d3 \∑ 0, d3 in the universal computable numbering of computable structures for the language with one binary predicate.
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Translated from Sibirskiĭ Matematicheskiĭ Zhurnal, Vol. 48, No. 5, pp. 1167–1179, September–October, 2007.
Original Russian Text Copyright © 2007 Fokina E. B.
The author was partially supported by the Russian Foundation for Basic Research (Grant 05-01-00819) and the State Maintenance Program for the Leading Scientific Schools of the Russian Federation (Grant NSh-4413.2006.1).
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Fokina, E.B. Index sets of decidable models. Sib Math J 48, 939–948 (2007). https://doi.org/10.1007/s11202-007-0097-y
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DOI: https://doi.org/10.1007/s11202-007-0097-y