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arXiv · 1302.2036

On $π$-extensions of the semigroup $\mathbb{Z}_+$

T. A. Grigoryan·E. V. Lipacheva·V. H. Tepoyan
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Abstract

We study inverse $π$-extensions of the semigroup $\mathbb{Z}_+$. It is shown that $π$-extension of the semigroup $\mathbb{Z}_+$ is inverse, iff its $π$-extension coincides with $π(\mathbb{Z}_+)$. The existence of a non-inverse $π$-extension for semigroup $\mathbb{Z}_+$ is proved.

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T. A. Grigoryan, E. V. Lipacheva, V. H. Tepoyan. 2013-02-08. On $π$-extensions of the semigroup $\mathbb{Z}_+$. https://arxiv.org/abs/1302.2036

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