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 A223706 #3 Apr 03 2013 22:52:09
%S A223706 0,0,0,2,0,3,18,7,0,30,5,10,0,6,6205,0,178,13,29,0,8,23,0,0,35,102,46,
%T A223706 429,45,0,19,263,0,42,7600,32,12,58,1083163,520,0,48,880129,84,5320,
%U A223706 92,14,39,13848,94,4195,718,15,21085,772,502068,5381,28,116,5579256
%N A223706 Conjectured least number k such that prime(n) is the largest divisor of k^3 - 1, or 0 if there is no such k.
%C A223706 We allowed k to vary up to 10^7.
%t A223706 nn = 60; t = Table[0, {nn}]; ps = Prime[Range[nn]]; Do[num = n^3 - 1; j = 0; lastP = 0; While[num > 0 && j < nn, j++; p = ps[[j]]; While[Mod[num, p] == 0, lastP = j; num = num/p]];If[num == 1 && t[[lastP]] == 0, t[[lastP]] = n; Print[{lastP, n}]], {n, 10^7}]; t
%Y A223706 Cf. A223701-A223707 (related sequences).
%K A223706 nonn
%O A223706 1,4
%A A223706 _T. D. Noe_, Apr 03 2013