# 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} }

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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