Find the nth Aaron number
05AB1E, 11 10 9 bytes

-1 byte thanks to Emigna
-1 byte thanks to Adnan

µN&gt;Ð&lt;‚ÒOË


Explanation:

µ            While the counter variable (which starts at 0) is not equal to the input:
 N&gt;          Store the current iteration index + 1, and then create an array with
   Ð&lt;‚       [current iteration index + 1, current iteration index]
      ÒO     Get the sum of the prime factors of each element
        Ë    If all elements in the array are equal,
             implicitly increment the counter variable


1-indexed.

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