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 A056750 #7 Mar 12 2018 17:43:22
%S A056750 1,2,4,7,10,14,28,49,50,70,98,196,209,250,343,350,490,539,668,686,
%T A056750 1250,1309,1372,1519,1750,1919,2401,2450,2690,2849,3430,4450,4802,
%U A056750 6250,8750,9212,9590,9604,9982,10717,12250,15698,16807,17150,18790,24010,31250
%N A056750 Numbers n such that n | 7^n + 6^n + 5^n + 4^n + 3^n + 2^n + 1^n.
%t A056750 Do[ If[ Mod[ PowerMod[ 7, n, n ] + PowerMod[ 6, n, n ] + PowerMod[ 5, n, n ] + PowerMod[ 4, n, n ] + PowerMod[ 3, n, n ] + PowerMod[ 2, n, n ] + 1, n ] == 0, Print[ n ] ], {n, 1, 10^6} ]
%t A056750 Select[Range[31500],Divisible[Plus@@(Range[7]^#),#]&] (* or *) Select[ Range[ 31500],Mod[Total[PowerMod[Range[7],#,#]],#]==0&] (* The second program is much faster than the first, and the second program is only a rewrite of the first program above *) (* _Harvey P. Dale_, Mar 12 2018 *)
%Y A056750 Cf. A001554.
%K A056750 nonn
%O A056750 1,2
%A A056750 _Robert G. Wilson v_, Aug 25 2000