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Algebra and Logic

, 50:279 | Cite as

Turing jumps in the Ershov hierarchy

  • M. Kh. FaizrakhmanovEmail author
Article
  • 32 Downloads

We look at infinite levels of the Ershov hierarchy in the natural system of notation, which are proper for jumps of sets. It is proved that proper infinite levels for jumps are confined to \( \Delta_a^{ - 1} \) -levels, where a stands for an ordinal ωn > 1.

Keywords

Turing jumps Ershov hierarchy constructive ordinals superlow sets 

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Copyright information

© Springer Science+Business Media, Inc. 2011

Authors and Affiliations

  1. 1.Kazan (Volga Region) Federal UniversityKazanRussia

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