摘要: 20201201A组T3(过程推导) \[ \begin{equation}\begin{aligned}&\sum_{i=1}^{n}\sum_{j=1}^{m}gcd^n(i,j)\sum_{k=1}^{ij}[i \bot k][j \bot k]k\\ &=\sum_{i=1}^{n}\su 阅读全文
posted @ 2020-12-01 21:53 Kelvin2005 阅读(78) 评论(0) 推荐(0)