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arXiv · 1311.5967

Dual F-signature of special Cohen-Macaulay modules over cyclic quotient surface singularities

Yusuke Nakajima
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Abstract

The notion of $F$-signature is defined by C. Huneke and G. Leuschke and this numerical invariant characterizes some singularities. This notion is extended to finitely generated modules and called dual $F$-signature. In this paper, we determine the dual $F$-signature of a certain class of Cohen-Macaulay modules (so-called "special") over cyclic quotient surface singularities. Also, we compare the dual $F$-signature of a special Cohen-Macaulay module with that of its Auslander-Reiten translation. This gives a new characterization of the Gorensteiness.

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Yusuke Nakajima. 2013-11-23. Dual F-signature of special Cohen-Macaulay modules over cyclic quotient surface singularities. https://arxiv.org/abs/1311.5967

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