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arXiv · 1012.5329

Edge ideals: algebraic and combinatorial properties

Susan Morey·Rafael H. Villarreal
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Abstract

Let C be a clutter and let I(C) be its edge ideal. This is a survey paper on the algebraic and combinatorial properties of R/I(C) and C, respectively. We give a criterion to estimate the regularity of R/I(C) and apply this criterion to give new proofs of some formulas for the regularity. If C is a clutter and R/I(C) is sequentially Cohen-Macaulay, we present a formula for the regularity of the ideal of vertex covers of C and give a formula for the projective dimension of R/I(C). We also examine the associated primes of powers of edge ideals, and show that for a graph with a leaf, these sets form an ascending chain.

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Susan Morey, Rafael H. Villarreal. 2011-03-29. Edge ideals: algebraic and combinatorial properties. https://doi.org/10.1515/9783110250404

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