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arXiv · 1401.2950

On a Problem of A. Nagy

Attila Deák
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Abstract

If the congruences of a semigroup are commutative, we say that the semigroup is permutable. In a previous paper, A. Nagy showed that every permutable semigroup satisfying an arbitrary non-trivial permutation identity is medial or an ideal extension of a rectangular band by a non-trivial commutative nil semigroup. The author raised the following problem: Is every permutable semigroup satisfying a non-trivial permutation identity medial? In present paper we give a positive answer for this problem.

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Attila Deák. 2014-01-10. On a Problem of A. Nagy. https://arxiv.org/abs/1401.2950

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