1. If M is a finite A-module, for example Z/6Z as a Z module, then M is Noetherian and Artinian
  2. Z is noetherian but not Artinan (In particular, every 1;;principal ideal domain A is noetherian and artinian iff A is a field).
  3. k[x] is a PID and not a field, so it is Noetherian but not Artinian
  4. Consider k[x1,x2,] in countably many variables. This ring is not Noetherian by construction. By what we will see next, since k[x1] is a quotient module of k[x1,x2,] which is not Artinian, the original ring is not Artinian.
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