Abstract
We describe an easy way to determine whether the realization of a set of idempotent identities guarantees congruence modularity or the satisfaction of a nontrivial congruence identity. Our results yield slight strengthenings of Day’s Theorem and Gumm’s Theorem, which each characterize congruence modularity.
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Presented by R. Freese.
This material is based upon work supported by the Hungarian National Foundation for Scientific Research (OTKA) grant no. K77409.
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Dent, T., Kearnes, K.A. & Szendrei, Á. An easy test for congruence modularity. Algebra Univers. 67, 375–392 (2012). https://doi.org/10.1007/s00012-012-0186-z
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DOI: https://doi.org/10.1007/s00012-012-0186-z