Menon-type identities concerning subsets of the set $\{1,2,\ldots,n\}$

Abstract

We prove certain Menon-type identities associated with the subsets of the set $\{1,2,\ldots,n\}$ and related to the functions $f$, $f_k$, $\Phi$ and $\Phi_k$, defined and investigated by Nathanson (2007).