On Cyclic and Negacyclic Codes of Length 8ps Over Fpm + uFpm

In this paper, we establish the algebraic structure of all cyclic and negacyclic codes of length 8p^s over the chain ring Fp^m + uFp^m 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 8p^s over Fp^m + uFp^m. Also, we determine μ and -constacyclic codes of length 8p^s over Fp^m + uFp^m.