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Rees algebras and polyhedral cones of ideals of vertex covers of perfect graphs

Rafael H. Villarreal
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Abstract

Let G be a perfect graph and let J be its ideal of vertex covers. We show that the Rees algebra of J is normal and that this algebra is Gorenstein if G is unmixed. Then we give a description--in terms of cliques--of the symbolic Rees algebra and the Simis cone of the edge ideal of G.

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Rafael H. Villarreal. 2007-07-12. Rees algebras and polyhedral cones of ideals of vertex covers of perfect graphs. https://arxiv.org/abs/math/0607329

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