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arXiv · 0706.0248

Aperiodic Pointlikes and Beyond

Karsten Henckell·John Rhodes·Benjamin Steinberg
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Abstract

We prove that if $π$ is a recursive set of primes, then pointlike sets are decidable for the pseudovariety of semigroups whose subgroups are $π$-groups. In particular, when $π$ is the empty set, we obtain Henckell's decidability of aperiodic pointlikes. Our proof, restricted to the case of aperiodic semigroups, is simpler than the original proof.

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Karsten Henckell, John Rhodes, Benjamin Steinberg. 2007-06-17. Aperiodic Pointlikes and Beyond. https://arxiv.org/abs/0706.0248

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