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%I #5 Feb 23 2023 08:39:34
%S 1,2,3,9,10,27,50,81,230,243,250,310,610,729,1250,1550,2187,3050,4850,
%T 6250,6561,7550,7750,9610,15250,18910,19683,20450,31041,31250,31671,
%U 35650,37210,37750,38750,48050,58833,59049,76250,94550
%N Numbers n such that n | 5^n + 4^n + 3^n.
%t Select[ Range[ 10^5 ], Mod[ PowerMod[ 5, #, # ] + PowerMod[ 4, #, # ] + PowerMod[ 3, #, # ], # ] == 0 & ]
%t Select[Range[100000],Mod[Total[PowerMod[Range[3,5],#,#]],#]==0&] (* _Harvey P. Dale_, Feb 23 2023 *)
%K nonn
%O 1,2
%A _Robert G. Wilson v_, Sep 20 2000