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arXiv · 1907.02348

The Huneke-Wiegand conjecture and middle terms of almost split sequences

Toshinori Kobayashi
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Abstract

Let R be a Gorenstein local domain of dimension one. We show that a nonfree maximal Cohen--Macaulay R-module M possessing more than one nonfree indecomposable summand in the middle term of the almost split sequence ending in M has a nonvanishing self extension. In other words, we show that the Huneke--Wiegand conjecture is affirmative for such R-modules M.

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Toshinori Kobayashi. 2019-07-04. The Huneke-Wiegand conjecture and middle terms of almost split sequences. https://arxiv.org/abs/1907.02348

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