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%I #10 Dec 08 2016 11:31:31
%S 1,2,2,3,4,5,3,2,6,7,8,9,10,11,5,2,12,13,14,6,15,3,16,17,18,7,19,20,
%T 21,22,8,23,24,25,26,27,28,29,30,31,10,32,33,34,35,36,11,37,38,39,40,
%U 41,12,42,43,44,45,2,46,3,13,47,48,49,50,51,52,14,53,54,55,5,56,57,58,15
%N a(n)^A072814(n) is the n-th perfect power.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PerfectPower.html">Perfect Power</a>.
%t {1}~Join~Map[Function[m, Function[w, 1 + Position[w, Min@ DeleteCases[w, x_ /; x < 2]][[1, 1]]]@ Table[Boole[k^# == m] # &@ IntegerExponent[m, k], {k, 2, Floor@ Sqrt@ m}]], Select[Range@ 3400, GCD @@ FactorInteger[#][[All, -1]] > 1 &]] (* _Michael De Vlieger_, Dec 08 2016 *)
%Y Cf. A001597(n) = a(n)^A072814(n).
%K nonn
%O 1,2
%A _Reinhard Zumkeller_, Jul 12 2002
%E Inserted a(1) = 1 by _Gionata Neri_, Dec 08 2016