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arXiv · 0810.4656

The Yoneda algebra of a K_2 algebra need not be another K_2 algebra

Thomas Cassidy·Christopher Phan·Brad Shelton
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Abstract

The Yoneda algebra of a Koszul algebra or a D-Koszul algebra is Koszul. K_2 algebras are a natural generalization of Koszul algebras, and one would hope that the Yoneda algebra of a K_2 algebra would be another K_2 algebra. We show that this is not necessarily the case by constructing a monomial K_2 algebra for which the corresponding Yoneda algebra is not K_2.

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Thomas Cassidy, Christopher Phan, Brad Shelton. 2008-11-11. The Yoneda algebra of a K_2 algebra need not be another K_2 algebra. https://doi.org/10.1080/00927870902829148

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