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 A178200 #12 Feb 12 2014 18:19:22
%S A178200 1,2,37,6,5,17,11,1514,31,12,29,70,159,26,85,21,23,94,33,1502,779,30,
%T A178200 253529023201,214,25,28,299,54,2905241561,115,77,298,96172711,48,
%U A178200 13243955,1486,63,106,1841252062709911,41,13343,74,59277,1478,119,82,697,134,69,176,70961,150,481,116,55,1466,3161,84,437,86,511,146,13787,153,90224135,104,6789,1454,140459,132,958471,1303310,87,362,175,482,1369,244,93,98,2501,88,119239,1438,1077,692,2258141,102,9066799,358,99,130,46859,506,121,217,187,124,163067,105,40649
%N A178200 Smallest k such that 39^k mod k = n.
%t A178200 aa = {}; Do[k = 1; While[PowerMod[39, k, k] != n, k++ ]; Print[{n, k}]; AppendTo[aa, k], {n, 1, 50}]; aa
%Y A178200 Cf. A036236, A078457, A119678, A119679, A119714-A119716, A127817-A127821, A128154-A128372, A178194-A178202
%K A178200 nonn
%O A178200 0,2
%A A178200 _Artur Jasinski_, May 23 2010
%E A178200 Terms a(22) onward from _Max Alekseyev_, Feb 04 2012, Apr 13 2012