Journal of Computer Science and Technology

, Volume 6, Issue 3, pp 285–290 | Cite as

Classification of the index sets of low[n] pand high[n] p

  • Sui Yuefei 
Regular Papers


In this paper we will first give the characterization of thep lowp degree, and prove that a p.r.e. degree
if and only if\(\underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle\thicksim}$}}{a} ' > p \underset{\raise0.3em\hbox{$\smash{\scriptscriptstyle\thicksim}$}}{o} '\). Then we classify the index sets of Low[n] p and High[n] p and prove that Low[n] p is\(\Sigma ^p [n + 3] - complete\) and High[n] p is\(\Sigma ^p [n + 4] - complete\).


Polynomial Time Recursive Function Computable Function Standard Enumeration 199t Classification 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Science Press 1991

Authors and Affiliations

  • Sui Yuefei 
    • 1
  1. 1.Institute of SoftwareAcademia SinicaBeijing

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