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arXiv · 1905.01151

Betti numbers of monomial ideals in four variables

Guillermo Alesandroni
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Abstract

We express the multigraded Betti numbers of monomial ideals in 4 variables in terms of the multigraded Betti numbers of 66 squarefree monomial ideals, also in 4 variables. We use this class of 66 ideals to prove that monomial resolutions in 4 variables are independent of the base field. In addition, we give a formula for the Betti numbers of an arbitrary monomial ideal in 4 variables.

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Guillermo Alesandroni. 2019-05-03. Betti numbers of monomial ideals in four variables. https://arxiv.org/abs/1905.01151

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