I have only a small compendium with no more than 120 pages (10 different chapters) that covers an entire semester.
I see that for xt≡1 mod p, for p = 3, 5, 7, it follows a repetitive order whereas mod 15, 21, 35 does not.
For p = 3, q = 5, n=15, I see for the same value of x, the order...