Guy $(2004, p. 150)$ discussed solutions to $\phi(\sigma(n))=n $ ,In my below question I asked if he discussed also the solution of the below equation ,then I w'd like to seek for the pair of integers $( m, n)$ for which : $$\displaystyle \phi(\sigma(n))=m² $$ ?.
Note: $\displaystyle\sigma(n)=\sum_{d|n}d$ is sum divisor function ,and $\phi$ is Euler totiont function
Thank you for any help
fairly common
=================================================
==============================================