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arXiv · 1802.01884

Asymptotic invariants of ideals with Noetherian symbolic Rees algebra and applications to cover ideals

Ben Drabkin·Lorenzo Guerrieri
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Abstract

Let $I$ be an ideal whose symbolic Rees algebra is Noetherian. For $m \geq 1$, the $m$-th symbolic defect, sdefect$(I,m)$, of $I$ is defined to be the minimal number of generators of the module $\frac{I^{(m)}}{I^m}$. We prove that sdefect$(I,m)$ is eventually quasi-polynomial as a function in $m$. We compute the symbolic defect explicitly for certain monomial ideals arising from graphs, termed cover ideals. We go on to give a formula for the Waldschmidt constant, an asymptotic invariant measuring the growth of the degrees of generators of symbolic powers, for ideals whose symbolic Rees algebra is Noetherian.

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Ben Drabkin, Lorenzo Guerrieri. 2018-02-06. Asymptotic invariants of ideals with Noetherian symbolic Rees algebra and applications to cover ideals. https://arxiv.org/abs/1802.01884

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