Two structurally defined types of NP sets are studied. k-simple sets are defined and shown to exist in NP. Other properties of these sets are investigated. k-creative sets, as previously defined by Joseph and Young [10], are next considered. A new condition is given which implies that a set is k-creative. Several previously considered NP-complete sets are proved to be k-creative.


Turing Machine Step Simulation Infinite Subset Tiling Problem Recursive Enumeration 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1986

Authors and Affiliations

  • Steven Homer
    • 1
  1. 1.Computer Science DepartmentBoston UniversityBostonUSA

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