Siberian Mathematical Journal

, Volume 49, Issue 2, pp 239–245 | Cite as

e-Principal numberings

  • A. N. DëgtevEmail author
  • M. L. Platonov


We prove the existence of the computable families of finite sets and general recursive functions with no e-principal numbering. We give a series of examples of e-degrees such that the p-degrees of their computable numberings include no top p-degree.


partial recursive function recursively enumerable set computable numbering e-reducibility p-reducibility 


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Copyright information

© Springer Science+Business Media, Inc. 2008

Authors and Affiliations

  1. 1.Tyumen’ State UniversityTyumen’Russia

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