On Cyclic and Negacyclic Codes of Length 8p<sup>s</sup> Over Fp<sup>m</sup> + uFp<sup>m</sup>

In this paper, we establish the algebraic structure of all cyclic and negacyclic codes of length 8ps over the chain ring Fpm + uFpm in terms of their generator polynomials, where u2 = 0 and s is a positive integer and p is an odd prime. We also find out the number of codewords in each of these cyclic codes. Besides this, we determine duals of cyclic codes and list self-dual cyclic and negacyclic codes of length 8ps over Fpm + uFpm. Also, we determine μ and -constacyclic codes of length 8ps over Fpm + uFpm.