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 A174134 #2 Mar 30 2012 17:27:05 %S A174134 0,4,20,24,60,116,120,136,140,260,340,360,444,676,696,700,816,1040, %T A174134 1476,2020,2220,2280,2684,3480,3940,4056,4060,4080,4420,4756,5516, %U A174134 6100,6120,6460,6780,8224,8840,8976,9860,11700,13756,16040,18564,21340,22964 %N A174134 Nonnegative integers m such that m^2 = (a^2-1)*(b^2+1) for some integers a,b. %C A174134 m belongs to this sequence iff m^2 belongs to A174133. %C A174134 All terms are multiples of 4. %K A174134 nonn %O A174134 1,2 %A A174134 _Max Alekseyev_, Apr 01 2010