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arXiv · 2505.15608

Comparison of stability indices of powers of graded ideals

Antonino Ficarra·Emanuele Sgroi
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Abstract

In this paper, we compare the index of ass-stability $\text{astab}(I)$ and the index of $\text{v}$-stability $\text{vstab}(I)$ of powers of a graded ideal $I$. We prove that $\text{astab}(I)=1\le\text{vstab}(I)$ for any graded ideal $I$ in a 2-dimensional polynomial ring, and that $\text{vstab}(I)$ can be any positive integer in this situation. Moreover, given any integers $a,b\ge1$, we construct a graded ideal $I$ in a $3(a+1)$-dimensional polynomial ring such that $(\text{astab}(I),\text{vstab}(I))=(a,b)$.

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Antonino Ficarra, Emanuele Sgroi. 2025-05-21. Comparison of stability indices of powers of graded ideals. https://arxiv.org/abs/2505.15608

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