Let $\delta>0$. I am interested in obtaining a bound for the sum $\sum_{1 \leq x_1, ..., x_n \leq N} lcm(x_1, ..., x_n)^{- \delta}$$\sum_{1 \leq x_1, ..., x_n \leq N} \operatorname{lcm}(x_1, ..., x_n)^{- \delta}$ where lcm denotes the lowest common multiple of the numbers. I would appreciate any comments and suggestions! Thank you very much.