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arXiv · 1105.1452

The irrationality of a number theoretical series

Jan-Christoph Schlage-Puchta
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Abstract

Denote by $σ_k(n)$ the sum of the $k$-th powers of the divisors of $n$, and let $S_k=\sum_{n\geq 1}\frac{σ_k(n)}{n!}$. We prove that Schinzel's conjecture H implies that $S_k$ is irrational, and give an unconditional proof for the case $k=3$.

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Jan-Christoph Schlage-Puchta. 2011-05-07. The irrationality of a number theoretical series. https://doi.org/10.1007/s11139-006-0154-3

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