%I #3 Mar 30 2012 17:30:26
%S 1,2,3,9,10,22,27,50,57,81,243,250,530,729,1083,1250,2187,5750,6250,
%T 6561,15447,19683,20577,31250,42807,59049,84250,92283,105279,156250,
%U 177147,331250,390963,480411,530631,531441,536301,781250
%N Numbers n such that n | 7^n + 6^n + 5^n.
%t Select[ Range[ 10^6 ], Mod[ PowerMod[ 7, #, # ] + PowerMod[ 6, #, # ] + PowerMod[ 5, #, # ], # ] == 0 & ]
%K nonn
%O 1,2
%A _Robert G. Wilson v_, Sep 20 2000