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arXiv · 1103.0992

Associated primes of powers of edge ideals

Jose Martinez-Bernal·Susan Morey·Rafael H. Villarreal
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Abstract

Let G be a graph and let I be its edge ideal. Our main result shows that the sets of associated primes of the powers of I form an ascending chain. It is known that the sets of associated primes of I(i) and intcl(I(i)) stabilize for large i, where "intcl" denotes integral closure and I(i) denotes the i-th power of I. We show that for edge ideals their corresponding stable sets are equal. To show our main result we use a classical result of Berge from matching theory and certain notions from combinatorial optimization.

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Jose Martinez-Bernal, Susan Morey, Rafael H. Villarreal. 2011-03-04. Associated primes of powers of edge ideals. https://arxiv.org/abs/1103.0992

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