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arXiv · 2402.07931

On a problem of Pongsriiam on the sum of divisors

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 for every integer $ 1\leq k\leq 29,\ (k,30)=1, $ we have $$\sum_{n\leq K}\sigma(30n)>\sum_{n\leq K}\sigma(30n+k)$$ for all $K\in \mathbb{N},$ which gives a positive answer to a problem posed by Pongsriiam recently.

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BibTeXRIS

Rui-Jing Wang. 2024-02-06. On a problem of Pongsriiam on the sum of divisors. https://arxiv.org/abs/2402.07931

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