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arXiv · 2506.14633

On the Composition of the Euler Function and the Dedekind Arithmetic Function

Aimin Guo·Huan Liu·Qiyu Yang
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Abstract

Let $I(n) = \frac{\psi(\phi(n))}{\phi(\psi(n))}$ and $K(n) = \frac{\psi(\phi(n))}{\phi(\phi(n))}$, where $\phi(n)$ is Euler's function and $\psi(n)$ is Dedekind's arithmetic function. We obtain the maximal order of $I(n)$, as well as the average orders of $I(n)$ and $K(n)$. Additionally, we prove a density theorem for both $I(n)$ and $K(n)$.

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Aimin Guo, Huan Liu, Qiyu Yang. 2025-06-17. On the Composition of the Euler Function and the Dedekind Arithmetic Function. https://arxiv.org/abs/2506.14633

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