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arXiv · 1809.05473

Nonrepresentable relation algebras from group systems

H. Andréka·S. Givant·I. Németi
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Abstract

A series of nonrepresentable relation algebras is constructed from groups. We use them to prove that there are continuum many subvarieties between the variety of representable relation algebras and the variety of coset relation algebras. We present our main construction in terms of polygroupoids.

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H. Andréka, S. Givant, I. Németi. 2018-09-14. Nonrepresentable relation algebras from group systems. https://doi.org/10.1017/s1755020319000224

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