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The equality I^2=QI in Buchsbaum rings with multiplicity two

Shiro Goto·Hideto Sakurai
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Abstract

Let A be a Buchsbaum local ring with the maximal ideal m and let e(A) denote the multiplicity of A. Let Q be a parameter ideal in A and put I=Q:m. Then the equality I^2=QI holds true, if e(A)=2 and depthA>0. The assertion is no longer true, unless e(A)=2. Counterexamples are given.

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Shiro Goto, Hideto Sakurai. 2003-06-09. The equality I^2=QI in Buchsbaum rings with multiplicity two. https://arxiv.org/abs/math/0306146

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