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(Sum of distinct prime factors)^(sum of prime exponents).
5

%I #14 Apr 25 2017 19:00:32

%S 1,2,3,4,5,25,7,8,9,49,11,125,13,81,64,16,17,125,19,343,100,169,23,

%T 625,25,225,27,729,29,1000,31,32,196,361,144,625,37,441,256,2401,41,

%U 1728,43,2197,512,625,47,3125,49,343,400,3375,53,625,256,6561,484,961

%N (Sum of distinct prime factors)^(sum of prime exponents).

%C a(n) = n iff n is 1 or a prime power; otherwise, a(n) > n. - _Ivan Neretin_, May 31 2016

%H Ivan Neretin, <a href="/A088865/b088865.txt">Table of n, a(n) for n = 1..10000</a>

%F a(n) = A008472(n)^A001222(n).

%e a(75) = a(3^1 * 5^2) = (3+5)^(1+2) = 8^3 = 512.

%t pf2pe[n_]:=Module[{tfi=Transpose[FactorInteger[n]]},Total[ First[tfi]]^ Total[ Last[tfi]]]; Array[pf2pe,60] (* _Harvey P. Dale_, Sep 21 2011 *)

%t Array[Power @@ Map[Total, Transpose@ FactorInteger@ #] &, 58] (* _Michael De Vlieger_, Apr 25 2017 *)

%K nonn

%O 1,2

%A _Reinhard Zumkeller_, Nov 26 2003