DOI link for Periodic factorizations
Periodic factorizations book
In this chapter we consider finite cyclic groups. In Chapter 3 we showed that for certain orders of factors bad factorizations arise and claimed in Section 3.1 that these results were best possible. In order to justify this claim, the cases where we must show that one factor is necessarily periodic are as follows:
(i) Each factor has either prime power order or order equal to the product of two primes.