# On simple and creative sets in NP

Session 7 Complexity

First Online:

## Abstract

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.

## Keywords

Turing Machine Step Simulation Infinite Subset Tiling Problem Recursive Enumeration
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