For any given positive integer m, a necessary and sufficient condition for
the existence of Type I m-adic constacyclic codes is given. Further, for any
given integer s, a necessary and sufficient condition for s to be a
multiplier of a Type I polyadic constacyclic code is given. As an application,
some optimal codes from Type I polyadic constacyclic codes, including
generalized Reed-Solomon codes and alternant MDS codes, are constructed.Comment: We provide complete solutions on two basic questions on polyadic
constacyclic cdes, and construct some optimal codes from the polyadic
constacyclic cde
