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%I #26 Aug 19 2016 04:46:26
%S 4,16,64,65536,4096,18446744073709551616,16777216,68719476736,
%T 281474976710656
%N Smallest perfect power m for which there are exactly n ways to write m as x^y with x >= 2, y >= 1.
%C a(10) is 2^1024 and is too big to display. - _Joerg Arndt_, Aug 17 2016.
%F a(n) = 2^d(s) where s is the least number having d(s) = A000005(s) = n. - _David A. Corneth_, Aug 17 2016
%F a(n) = 2^A005179(n). - _Joerg Arndt_, Aug 17 2016
%e For n = 6, a(6) = 4096: there are 6 ways to write 4096 as x^y: 4096^1 = 64^2 = 16^3 = 8^4 = 4^6 = 2^12.
%e a(7) = 2^64, a(8) = 16777216. See A175064, A001597.
%Y Cf. A000005, A001597, A175064.
%K nonn
%O 2,1
%A _Jaroslav Krizek_, Jan 23 2010
%E More terms from _David A. Corneth_ and _Joerg Arndt_, Aug 17 2016
%E Edited by _N. J. A. Sloane_, Aug 18 2016
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