#!/usr/bin/env python3 def transform(n, loopsize): return pow(n, loopsize, 20201227) def loopsize(transformed): n = size = 1 while True: n = n * 7 % 20201227 if n == transformed: return size size += 1 a, b = 9789649, 3647239 print(transform(a, loopsize(b)))