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arXiv · 1504.07688

Ulrich modules over cyclic quotient surface singularities

Yusuke Nakajima·Ken-ichi Yoshida
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Abstract

In this paper, we characterize Ulrich modules over cyclic quotient surface singularities by using the notion of special Cohen-Macaulay modules. We also investigate the number of indecomposable Ulrich modules for a given cyclic quotient surface singularity, and show that the number of exceptional curves in the minimal resolution gives a boundary for the number of indecomposable Ulrich modules.

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Yusuke Nakajima, Ken-ichi Yoshida. 2015-04-29. Ulrich modules over cyclic quotient surface singularities. https://arxiv.org/abs/1504.07688

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