欧拉函数求和 - Problem Detail - 算道OJ

ID: 14326

Type: RemoteJudge

1000ms

256MiB

Difficulty: (None)

Uploaded By:

题目描述

给出一个数字N，求sigma(phi(i)),1<=i<=N

输入格式

正整数N。N<=2*10^9

输出格式

输出答案。