The ‘almost all’ theory of subrecursive degrees is decidable

  • Kurt Mehlhorn
Wednesday Morning
Part of the Lecture Notes in Computer Science book series (LNCS, volume 14)


We use constructive measure theory to show the decidability of the ‘almost all’ theory of subrecursive degrees. The formulas of this theory are built up using the constant 0 standing for the minimum degree, the functions ∪, ν standing for the join and meet of two degrees respectively, the relation ≤ standing for the reducibility the logical connectives &, ⌍, and the quantifier (for almost all a). An efficient decision procedure is described.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1974

Authors and Affiliations

  • Kurt Mehlhorn
    • 1
  1. 1.Department of Computer ScienceCornell UniversityIthaca

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