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arXiv · 1208.5158

On the constancy regions for mixed test ideals

Felipe Pérez
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Abstract

In this note we study the partition of $\mathbb{R}_{\geq0}^{n}$ given by the regions where the mixed test ideals $τ(\mathfrak{a}_{1}^{t_{1}}... \mathfrak{a}_{n}^{t_{n}})$ are constant. We show that each region can be described as the preimage of a natural number under a p-fractal function $φ:\mathbb{R}_{\geq0}^{n}\rightarrow\mathbb{N}$. In addition, we give some examples illustrating that these regions do not need to be composed of finitely many rational polytopes.

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Felipe Pérez. 2012-12-04. On the constancy regions for mixed test ideals. https://arxiv.org/abs/1208.5158

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