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 A175902 #7 Nov 04 2013 11:08:11
%S A175902 5,5,11,4,11,29,11,25,13,23,29,34,13,89,13,51,11,151,43,89,181,169,89,
%T A175902 29,101,59,223,111,181,269,125,29,23,101,83,35,56,305,79,113,181,287,
%U A175902 151,155,379,349,769,545,329,505,571,37,373,769,344,91,1121,79,353,79,985
%N A175902 Values of k in A175901.
%o A175902 (PARI) isok(n) = {pfs = factor(n^2-1)[,1]; for (k = 2, n-1, if (factor(k^2-1)[,1] == pfs, return (k));); return (0);}
%o A175902 lista(nn) = {for(n=2, nn, if (k = isok(n), print1(k, ", ");););} \\ _Michel Marcus_, Nov 04 2013
%Y A175902 Cf. A175607, A175901-A175904, A181447-A181471.
%K A175902 nonn
%O A175902 1,1
%A A175902 _Artur Jasinski_, Oct 11 2010, Oct 21 2010
%E A175902 Edited by _N. J. A. Sloane_, Oct 14 2010