摘要: \(A(x)=\sum x^{a_i}=\frac{x^{l_i}-x^{r_i+1}}{1-x}\) \[ F=\frac{1}{24}(\\ A(x)^4-\\ 6\cdot A(x)^2A(x^2)+\\ 3\cdot A(x^2)^2+\\ 8\cdot A(x^3)A(x)-\\ 6A(x 阅读全文
posted @ 2021-12-19 23:04 WWW~~~ 阅读(43) 评论(0) 推荐(0) 编辑