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arXiv · 1606.04293

Computability of Følner sets

Matteo Cavaleri
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Abstract

We define the notion of computability of Følner sets for finitely generated amenable groups. We prove, by an explicit description, that the Kharlampovich group, a finitely presented solvable group with unsolvable word problem, has computable Følner sets. We also prove computability of Følner sets for a group that is extension of an amenable group with solvable word problem by a finitely generated group with computable Følner sets with subrecursive distortion function. Moreover we obtain some known and some new upper bounds for the Følner function in these particular extensions.

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Matteo Cavaleri. 2017-03-15. Computability of Følner sets. https://doi.org/10.1142/s0218196717500382

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