Qiyu Yang

collaborators

2 papers

math.NT2025

An improved upper bound for the distribution of iterated Euler totient functions

Pei Gao, Qiyu Yang

Let $I ¨ (n)$ be the Euler totient function and $I ¨ _{k} (n)$ its $k$ -fold iterate. In this note, we improve the upper bound for the number of positive $n ⩽ x$ such that $Ï_{k+1}…

math.NT2025

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

Aimin Guo, Huan Liu, Qiyu Yang

Let $I (n) = \frac{I ¨ ( I ¨ ( n ))}{I ¨ ( I ¨ ( n ))}$ and $K (n) = \frac{I ¨ ( I ¨ ( n ))}{I ¨ ( I ¨ ( n ))}$ , where $I ¨ (n)$ is Euler's function and $I ¨ (n)$ is Dedekind's arithmetic function. We obtain the ma…