Abstract
We prove bounds for the popularity of products of sets with weak additive structure, and use these bounds to prove results about continued fractions. Namely, considering Zaremba’s set modulo p, that is the set of all a such that \({a \over p} = [{a_1}, \ldots ,{a_s}]\) has bounded partial quotients, aj ⩽ M, we obtain a sharp upper bound for the cardinality of this set.
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Moshchevitin, N., Murphy, B. & Shkredov, I. Popular products and continued fractions. Isr. J. Math. 238, 807–835 (2020). https://doi.org/10.1007/s11856-020-2039-3
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DOI: https://doi.org/10.1007/s11856-020-2039-3