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

2024/08/02 by Rui-Jing Wang, Wang, Rui-Jing
Mathematics · #Advanced Algebra and Geometry #Advanced Mathematical Identities #Analytic Number Theory Research #FOS: Mathematics #Number Theory (math.NT)

paper · pdf · doi:10.48550/arxiv.2408.00979

openalex publication_date 2024/08/02 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28

Abstract

For any positive integer n, let σ(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 σ(30n+1)≥ σ(30n) has a density less than 0.0371813, which answers a recent problem of Pongsriiam in part.

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