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Towards Commutator theory for relations. IV

Paolo Lipparini
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Abstract

We provide more characterizations of varieties having a term Mal'cev modulo two functions $F$ and $G$. We characterize varieties neutral in the sense of $F$, that is varieties satisfying $R \subseteq F(R)$. We present examples of global operators satisfying the homomorphism property, in particular we show that many known commutators satisfy the homomorphism property.

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Paolo Lipparini. 2006-12-17. Towards Commutator theory for relations. IV. https://arxiv.org/abs/math/0612483

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