Let $f(n)$ be the largest prime factor of $n$ and $\displaystyle F(n) = \sum_{i=2}^n f(i)$.
For example $F(10)=32$, $F(100)=1915$ and $F(10000)=10118280$.
Find $F(201820182018)$. Give your answer modulus $10^9$.
Solution
No solution yet. Write yours at
solutions/s642.md.