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Abstract

We prove that, for any ε > 0, it is NP-hard to, given a satisfiable instance of Max-NTW (Not-2), find an assignment that satisfies a fraction \(\frac 58 +\epsilon\) of the constraints. This, up to the existence of ε, matches the approximation ratio obtained by the trivial algorithm that just picks an assignment at random and thus the result is tight. Said equivalently the result proves that Max-NTW is approximation resistant on satisfiable instances and this makes our understanding of arity three Max-CSPs with regards to approximation resistance complete.

Keywords

Constraint Satisfaction Problem Correlate Space Extended Game Approximation Resistance Label Cover 
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

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Johan Håstad
    • 1
  1. 1.KTH Royal Institute of TechnologySweden

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