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%I #16 Nov 17 2018 20:45:31
%S 1,2,25,70,106,268,304,358,1559,2369,2824,2855,3616,5218
%N Numbers k such that k divides the sum of digits of 8^k.
%C The next term, if it exists, is greater than 100000. - _Ryan Propper_, Aug 31 2005
%C No further terms less than 1000000 using the same method _Donovan Johnson_ explains in A175525.
%e 25 divides the sum of digits of 8^25 (i.e., 3+7+7+7+8+9+3+1+8+6+2+9+5+7+1+6+1+7+0+9+5+6+8 = 125), so 25 is in the sequence.
%t k = 1; Do[k *= 8; s = Plus @@ IntegerDigits[k]; If[Mod[s, n] == 0, Print[n]], {n, 1, 10^5}] (* _Ryan Propper_, Aug 31 2005 *)
%K hard,nonn,base
%O 1,2
%A _Shyam Sunder Gupta_ and _Amarnath Murthy_, Feb 16 2002
%E Corrected and extended by _Ryan Propper_, Aug 31 2005
%E Edited by _Jon E. Schoenfield_, May 29 2010
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