This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A057233 #6 Jan 31 2020 09:12:25 %S A057233 1,3,7,9,21,27,49,51,63,81,147,189,243,343,441,567,729,931,1029,1323, %T A057233 1593,1701,2187,2349,2401,2493,2499,3087,3969,4077,4131,5103,6561, %U A057233 7203,9261,11907,15309,16807,19683,21609,27783,31743,35721,45927,50421 %N A057233 Numbers n such that n | 8^n + 7^n + 6^n. %H A057233 Robert Israel, <a href="/A057233/b057233.txt">Table of n, a(n) for n = 1..238</a> %p A057233 select(n -> 6 &^ n + 7 &^ n + 8 &^ n) mod n = 0, [$1..10^5]); # _Robert Israel_, Jan 30 2020 %t A057233 Select[ Range[ 10^6 ], Mod[ PowerMod[ 8, #, # ] + PowerMod[ 7, #, # ] + PowerMod[ 6, #, # ], # ] == 0 & ] %Y A057233 Contains A003594. %K A057233 nonn %O A057233 1,2 %A A057233 _Robert G. Wilson v_, Sep 20 2000