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arXiv · 1711.00184

On the denominators of harmonic numbers

Bing-Ling Wu·Yong-Gao Chen
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Abstract

Let $H_n$ be the $n$-th harmonic number and let $v_n$ be its denominator. It is well known that $v_n$ is even for every integer $n\ge 2$. In this paper, we study the properties of $v_n$. One of our results is: the set of positive integers $n$ such that $v_n$ is divisible by the least common multiple of $1, 2, \cdots, \lfloor {n^{1/4}}\rfloor $ has density one. In particular, for any positive integer $m$, the set of positive integers $n$ such that $v_n$ is divisible by $m$ has density one.

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Bing-Ling Wu, Yong-Gao Chen. 2017-11-01. On the denominators of harmonic numbers. https://doi.org/10.1016/j.crma.2018.01.005

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