## Gcd sum

### Problem 625

$G(N)=\sum_{j=1}^N\sum_{i=1}^j \text{gcd}(i,j)$.

You are given: $G(10)=122$.

Find $G(10^{11})$. Give your answer modulo 998244353

$G(N)=\sum_{j=1}^N\sum_{i=1}^j \text{gcd}(i,j)$.

You are given: $G(10)=122$.

Find $G(10^{11})$. Give your answer modulo 998244353