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arXiv · 1901.02548

Rough integers with a divisor in a given interval

Kevin Ford
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Abstract

We determine, up to multiplicative constants, the number of integers $n\le x$ that have no prime factor $\le w$ and a divisor in $(y,2y]$. Our estimate is uniform in $x,y,w$. We apply this to determine the order of the number of distinct integers in the $N\times N$ multiplication table which are free of prime factors $\le w$, and the number of distinct fractions of the form $\frac{a_1a_2}{b_1b_2}$ with $1\le a_1 \le b_1\le N$ and $1\le a_2\le b_2 \le N$.

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Kevin Ford. 2019-01-08. Rough integers with a divisor in a given interval. https://arxiv.org/abs/1901.02548

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