A certain reciprocal power sum is never an integer

Junyong Zhao, Shaofang Hong, Xiao Jiang

By $({\mathbb{Z}}^{+}{)}^{\infty }$ we denote the set of all the infinite sequences $\mathcal{S}=\{s_i{\}}_{i=1}^{\infty }$ of positive integers (note that all the $s_i$ are not necessarily…