Abstract
A sequence of integers is called a T-sequence if there exists a Hausdorff group topology on the integers such that the sequence converges to 0. Given a finite set S of primes, we construct some Hausdorff group topology on the integers such that every increasing sequence with terms divisible only by primes from S converges to 0. Also we answer in the affirmative the question on T-sequences which was posed by Protasov and Zelenuk. Our results rely on a nontrivial number-theoretic fact about S-unit equations.
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Russian Text © The Author(s), 2020, published in Sibirskii Matematicheskii Zhurnal, 2020, Vol. 61, No. 3, pp. 687–691.
The work was supported by the Program of Fundamental Scientific Research of the Russian Federation (Project 0314-2019-0001).
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Skresanov, S.V. Group Topologies on the Integers and S-Unit Equations. Sib Math J 61, 542–544 (2020). https://doi.org/10.1134/S0037446620030179
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DOI: https://doi.org/10.1134/S0037446620030179