## Basic operations - [x] FFT - [x] inv - [x] log - [x] exp - [ ] sqrt - [ ] pow ## Problems - [x] https://www.luogu.com.cn/problem/P5900 (http://oeis.org/A000081) - [x] https://www.luogu.com.cn/problem/P6295 (http://oeis.org/A082402)
