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arXiv · 0910.4597

A formula for the *-core of an ideal

Louiza Fouli·Janet C. Vassilev·Adela-N. Vraciu
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Abstract

Expanding on the work of Fouli and Vassilev \cite{FV}, we determine a formula for the *-$\rm{core}$ of an ideal in two different settings: (1) in a Cohen--Macaulay local ring of characteristic $p>0$, perfect residue field and test ideal of depth at least two, where the ideal has a minimal *-reduction that is a parameter ideal and (2) in a normal local domain of characteristic $p>0$, perfect residue field and $\m$-primary test ideal, where the ideal is a sufficiently high Frobenius power of an ideal. We also exhibit some examples where our formula fails if our hypotheses are not met.

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Louiza Fouli, Janet C. Vassilev, Adela-N. Vraciu. 2009-10-23. A formula for the *-core of an ideal. https://arxiv.org/abs/0910.4597

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