Prime Powers of Primes
05AB1E (legacy), &nbsp;9&nbsp; 7 bytes

Saved 2 bytes thank to @KevinCruijssen

µNÓ0Kp»


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µ           # while counter_variable != input:
 N          #   push iteration counter                       e.g. 125
  Ó         #   get prime exponents                          -&gt; [0, 0, 3]
   0K       #   filter out zeros                             -&gt; [3]
     p      #   is prime?                                    -&gt; [1]
      »     #   join with newlines: we use » instead of J
            #   so that [0,1] is not interpreted as truthy   -&gt; 1
            #   implicit: if 1, increment counter_variable