# A better approximation ratio for the vertex cover problem

@article{Karakostas2009ABA,
title={A better approximation ratio for the vertex cover problem},
author={George Karakostas},
journal={Electron. Colloquium Comput. Complex.},
year={2009}
}
• George Karakostas
• Published 2009
• Computer Science, Mathematics
• Electron. Colloquium Comput. Complex.
We reduce the approximation factor for the vertex cover to 2 − Θ (1/&sqrt;logn) (instead of the previous 2 − Θ ln ln n/2ln n obtained by Bar-Yehuda and Even [1985] and Monien and Speckenmeyer [1985]). The improvement of the vanishing factor comes as an application of the recent results of Arora et al. [2004] that improved the approximation factor of the sparsest cut and balanced cut problems. In particular, we use the existence of two big and well-separated sets of nodes in the solution of the… Expand
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