Published online by Cambridge University Press: 18 May 2009
This paper treats factorization and congruence in the arithmetics of Cayley's algebra C. Results, proved by Rankin [10], on the number of factorizations of a given element in the nonmaximal arithmetics Ho and Jo are reviewed. Further, new results on congruence are established and are used to find the number of factorizations of a prescribed element in the remaining arithmetics, including the maximal arithmetics Jw When computer factorizing a given element, the congruence results can be used as a heuristic device to prune the search tree.