Groups of prime-fourth order

This article is about the groups of prime-fourth order for an odd prime number, i.e., the groups of order $$p^4$$ where $$p$$ is an odd prime. The special case $$p = 2$$ is somewhat different -- see groups of order 16 for a summary of information on these groups.

Among the odd primes $$p$$, the case $$p = 3$$ is slightly different from the other primes.