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arXiv · 1404.5477

On the characterization of Jónsson-Tarski and of subtractive varieties

Marino Gran·Diana Rodelo
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Abstract

We investigate unital, subtractive and strongly unital regular categories with enough projectives and give characterizations of their projective covers. The categorical equation "strongly unital = unital + subtractive" is explored: this leads to proofs of their varietal characterizations in terms of the categorical properties of the corresponding algebraic theories.

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Marino Gran, Diana Rodelo. 2014-04-22. On the characterization of Jónsson-Tarski and of subtractive varieties. https://arxiv.org/abs/1404.5477

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