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arXiv · 1402.4052

Local rings of embedding codepth 3: a classification algorithm

Lars Winther Christensen·Oana Veliche
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Abstract

Let I be an ideal of a regular local ring Q with residue field k. The length of the minimal free resolution of R=Q/I is called the codepth of R. If it is at most 3, then the resolution carries a structure of a differential graded algebra, and the induced algebra structure on $Tor_Q(R,k) provides for a classification of such local rings. We describe the Macaulay2 package CodepthThree that implements an algorithm for classifying a local ring as above by computation of a few cohomological invariants.

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Lars Winther Christensen, Oana Veliche. 2014-02-17. Local rings of embedding codepth 3: a classification algorithm. https://doi.org/10.2140/jsag.2014.6.1

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