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 A057491 #17 Nov 30 2022 11:20:39 %S A057491 1,2,4,10,17,50,62,221,250,253,289,290,316,697,764,1250,1819,3590, %T A057491 4913,6250,31250,54043,55913,63869,83521,98923,156250,231250,530893, %U A057491 781250,987110,1419857,2383750,3906250,4531250,6891250,8789357,9593750,12479450,18458141,19531250 %N A057491 Numbers k such that k | 12^k + 11^k + 10^k + 9^k + 8^k + 7^k + 6^k + 5^k. %t A057491 Select[Range[1000000],Divisible[Total[PowerMod[Range[5,12],#,#]],#]&] (* _Harvey P. Dale_, Mar 28 2012 *) %o A057491 (Python) %o A057491 [n for n in range(1,20000000) if sum(pow(k,n,n) for k in range(5,13)) % n == 0] # _Lucas A. Brown_, Nov 30 2022 %Y A057491 Cf. A057490. %K A057491 nonn %O A057491 1,2 %A A057491 _Robert G. Wilson v_, Sep 22 2000 %E A057491 a(32)-a(42) from _Lucas A. Brown_, Nov 30 2022