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摘要: 题目要求: \[ \text{Ans}=\sum_{i=1}^N\sum_{j=1}^N\sum_{p=1}^{\lfloor\frac{N}{j}\rfloor}\sum_{q=1}^{\lfloor\frac{N}{j}\rfloor}[{\rm{gcd}}(i,j)=1][{\rm{gcd}} 阅读全文
posted @ 2020-08-22 22:48 GoPoux 阅读(110) 评论(0) 推荐(0)