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%I #9 Nov 21 2017 21:34:58
%S 1,2,3,5,6,7,8,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,26,27,28,
%T 29,30,31,33,34,35,37,38,39,40,41,42,43,44,45,46,47,48,50,51,52,53,54,
%U 55,56,57,58,59,60,61,62,63,64,65,66,67,68,69,70,71,72,73,74,75,76,77,78
%N Possible values for product of perfect divisors of n.
%C Perfect divisor of n is divisor d such that d^k = n for some k >= 1. All terms of this sequence occur only once. See A089723 (number of perfect divisors of n) and A175068 (product of perfect divisors of n).
%C Complement of A175085. - _Jaroslav Krizek_, Jan 30 2010
%t With[{nn = 78}, TakeWhile[#, # <= nn &] &@ Union@ Table[Apply[Times, Select[Divisors@ n, Or[# == 1, #^IntegerExponent[n, #] == n] &]], {n, nn}] ] (* _Michael De Vlieger_, Nov 21 2017 *)
%Y Cf. A175087 (characteristic function).
%K nonn
%O 1,2
%A _Jaroslav Krizek_, Jan 24 2010