# Some optimal inapproximability results

@article{Hstad2001SomeOI, title={Some optimal inapproximability results}, author={Johan H{\aa}stad}, journal={Electron. Colloquium Comput. Complex.}, year={2001}, volume={TR97} }

We prove optimal, up to an arbitrary ε > 0, inapproximability results for Max-E k-Sat for k ≥ 3, maximizing the number of satisfied linear equations in an over-determined system of linear equations modulo a prime p and Set Splitting. As a consequence of these results we get improved lower bounds for the efficient approximability of many optimization problems studied previously. In particular, for Max-E2-Sat, Max-Cut, Max-di-Cut, and Vertex cover.

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