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Third Mac Lane cohomology via categorical rings

Mamuka Jibladze·Teimuraz Pirashvili
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Abstract

It is proved that the third Mac Lane cohomology group of a ring R with coefficients in a bimodule B classifies categorical rings having R as the ring of isomorphism classes of objects and B as the bimodule of automorphisms of the neutral object.

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Mamuka Jibladze, Teimuraz Pirashvili. 2006-08-21. Third Mac Lane cohomology via categorical rings. https://arxiv.org/abs/math/0608519

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