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arXiv · 1504.06232

Multiplicative subsemigroups of the positive integers closed with respect to the number of digits

Simone Ugolini
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Abstract

In this paper we present an alternative approach to a problem dealt with by Rosales et al. In particular, once a base $b$ for the representation of the integers is fixed, we describe a procedure for constructing the smallest multiplicative subsemigroup of the positive integers closed with respect to the number of digits which contains a set of positive integers.

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Simone Ugolini. 2015-04-23. Multiplicative subsemigroups of the positive integers closed with respect to the number of digits. https://arxiv.org/abs/1504.06232

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