The characteristic number of a sequence of integers satisfying a linear recursion relation
Morgan Ward · Transactions of the American Mathematical Society · 1931
we shall call (A)n the reduced sequence corresponding to (W)n modulo m. If after s terms in the reduced sequence, a cycle of t terms keeps repeating itself indefinitely, (W)n will be said to admit the period t, modulo m. The least period that (W)n admits (modulo m) is called its characteristic number.t In this paper, I give a number of new results on the form of the characteristic number of a sequence. The principal result is the following: