Hello. There used to be a tutorial on the Extended Eratosthenes Sieve technique at https://www.spoj.com/problems/TEES/. I'm unsure what happened to it. Does anyone have a backup of either the tutorial or the Codeforces blog on it? If there is an alternative tutorial on the topic, that would also be welcomed as well.
Update: I found the post, but in image format.
Reposting below to preserve the post for myself and in case others are interested.
The Extended Eratosthenes Sieve technique allows us to efficiently find the partial sum of a multiplicative function.
Found image on: https://blog.csdn.net/BlackJack_/article/details/79872033
Original link: https://www.spoj.com/problems/TEES/