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arXiv · 2408.00979

On a problem of Pongsriiam on the sum of divisors, II

Rui-Jing Wang
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Abstract

For any positive integer $n$, let $\sigma (n)$ be the sum of all positive divisors of $n.$ In this paper, it is proved that the set of positive integers $ n $ for which $ \sigma(30n+1)\geq \sigma(30n) $ has a density less than $ 0.0371813, $ which answers a recent problem of Pongsriiam in part.

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Rui-Jing Wang. 2024-08-02. On a problem of Pongsriiam on the sum of divisors, II. https://arxiv.org/abs/2408.00979

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