摘要: \(\color{brown}{Link}\) \(\text{Solution:}\) \(Question:\) \(\prod_{i=1}^n \prod_{j=1}^n \frac{lcm(i,j)}{gcd(i,j)}\) 分开得: \(\frac{\prod_{i=1}^n \prod_ 阅读全文
posted @ 2020-07-22 17:12 Refined_heart 阅读(111) 评论(0) 推荐(0) 编辑