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arXiv · 1511.01418

Ext-finite modules for weakly symmetric algebras with radical cube zero

Karin Erdmann
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Abstract

Assume $A$ is weakly symmetric, indecomposable, with radical cube zero and radical square non-zero. We show that such algebra of wild representation type does not have a non-projective module $M$ whose ext algebra is finite-dimensional. This gives a complete classification weakly symmetric indecomposable algebras which have a non-projective module whose ext algebra is finite-dimensional.

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Karin Erdmann. 2015-11-04. Ext-finite modules for weakly symmetric algebras with radical cube zero. https://doi.org/10.1017/s1446788716000331

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