Lifting the Exponent
(Lemma from MAA official solution, 2020 AIME I Problems/Problem 12)
Denote the highest power of prime that divides . Let be an odd prime, and let and be integers that are not multiples of such that . Let be a positive integer. Then .
For more conclusions, see https://en.wikipedia.org/wiki/Lifting-the-exponent_lemma
edit by ~ab_godder