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Single spot ideals of codimension 3 and long Bourbaki sequences

Yukihide Takayama
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Abstract

Let K be a field and S = K[x1,...,xn] be a polynomial ring. A single spot ideal I =< S is a graded ideal whose local cohomology H^i_\mm(S/I), i< dim S/I and \mm = (x1,...,xn), only has non-trivial value N, a finite length module, at i = depth S/I. We consider characterization of single spot ideals in terms of (long) Bourbaki sequences. The codimension 2 case has been fairly well investigated. In this paper, we focus on the codimension 3 case.

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Yukihide Takayama. 2003-03-31. Single spot ideals of codimension 3 and long Bourbaki sequences. https://arxiv.org/abs/math/0303384

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