Every Permutation CSP of arity 3 is Approximation Resistant

@article{Charikar2009EveryPC,
  title={Every Permutation CSP of arity 3 is Approximation Resistant},
  author={Moses Charikar and Venkatesan Guruswami and Rajsekar Manokaran},
  journal={2009 24th Annual IEEE Conference on Computational Complexity},
  year={2009},
  pages={62-73}
}
A permutation constraint satisfaction problem (permCSP) of arity k is specified by a subset Lambda of permutations on $\{1,2,\dots,k\}$. An instance of such a permCSP consists of a set of variables $V$ and a collection of constraints each of which is an ordered $k$-tuple of $V$. The objective is to find a global ordering $\sigma$ of the variables that maximizes the number of constraint tuples whose ordering (under $\sigma$) follows a permutation in $\Lambda$. This is just the natural extension… Expand
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