Eccoci.

Define $\operatorname{Co}(n)$ to be the maximal possible sum of a set of mutually co-prime elements from $\{1,2,\dots,n\}$.
For example $\operatorname{Co}(10)$ is $30$ and hits that maximum on the subset $\{1,5,7,8,9\}$.

You are given that $\operatorname{Co}(30) = 193$ and $\operatorname{Co}(100) = 1356$.

Find $\operatorname{Co}(200000)$.