摘要： 题目链接https://lydsy.com/JudgeOnline/problem.php?id=3529题解题目要求∑i=1n∑j=1mσ0(gcd⁡(i,j))[σ0(gcd⁡(i,j))≤a]\sum_{i=1}^n\sum_{j=1}^m \sigm... 阅读全文