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%I #32 Jul 15 2018 12:59:48
%S 0,1,2,3,4,5,6,7,8,9,17,18,20,22,25,26,27,28,31,34,35,36,40,43,45,46,
%T 53,54,58,63,64,68,71,80,81,82,85,86,90,91,94,97,98,103,104,106,107,
%U 108,117,118,126,127,133,134,135,136,140,142,143,146,152,154,155,157,160,163,169,170
%N Numbers n for which the sum of the digits of n^k, for some k, is equal to n.
%C Most of the values are conjectural. So far not much is proved about the function A247889. - _M. F. Hasler_ and _Robert Israel_, May 18 2017
%H Hans Havermann, <a href="/A124359/b124359.txt">Table of n, a(n) for n = 1..3600</a>
%H Hans Havermann, <a href="http://chesswanks.com/num/a124359.txt">Solutions (k) for the terms (n <= 20034) of this sequence</a>
%e 18^3 = 5832 and 5 + 8 + 3 + 2 = 18 (also 18^6 = 34012224 and 18^7 = 612220032).
%e Again 46^5 = 205962976 and 2 + 0 + 5 + 9 + 6 + 2 + 9 + 7 + 6 = 46.
%o (PARI) for(n=0,199,if(A247889(n),print1(n,", "))) \\ _Derek Orr_, Sep 25 2014
%o (PARI) select(A247889,[0..170]) \\ _M. F. Hasler_, May 18 2017
%Y Complement of A124367. Numbers for which A247889 is nonzero.
%K nonn,base
%O 1,3
%A _Paolo P. Lava_ and _Giorgio Balzarotti_, Oct 27 2006
%E Prepended a(1) = 0, offset corrected and more terms added by _Derek Orr_, Sep 25 2014
%E Edited by _M. F. Hasler_, May 18 2017
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