Definition:Prime Power

Definition
A prime power $p^n$ is a positive integer which is a prime number $p$ raised to the power $n$.

The list of prime powers begins:


 * $1, 2, 3, 4, 5, 7, 8, 9, 11, 13, 16, 17, 19, 23, 25, 27, 29, 31, 32, 37, 41, \ldots$