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arXiv · cs/0304026

A New Multilayered PCP and the Hardness of Hypergraph Vertex Cover

Abstract

Given a $k$-uniform hyper-graph, the E$k$-Vertex-Cover problem is to find the smallest subset of vertices that intersects every hyper-edge. We present a new multilayered PCP construction that extends the Raz verifier. This enables us to prove that E$k$-Vertex-Cover is NP-hard to approximate within factor $(k-1-ε)$ for any $k \geq 3$ and any $ε>0$. The result is essentially tight as this problem can be easily approximated within factor $k$. Our construction makes use of the biased Long-Code and is analyzed using combinatorial properties of $s$-wise $t$-intersecting families of subsets.

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BibTeXRIS

Irit Dinur, Venkatesan Guruswami, Subhash Khot, Oded Regev. 2003-04-19. A New Multilayered PCP and the Hardness of Hypergraph Vertex Cover. https://arxiv.org/abs/cs/0304026

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