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 A177829 #2 Mar 30 2012 17:26:35 %S A177829 2,28,47,49,135,173,225,258,375,384,439,507,525,545,552,570,577,583, %T A177829 600,629,665,691,784,818,855,886,1024,1050,1076,1095,1187,1245,1259, %U A177829 1306,1367,1448,1495,1501,1614,1618,1646,1655,1720,1812,1826,1832,1843,1861 %N A177829 Positions of 2 in A176983. %F A177829 A176983(A177829(n))=2. %Y A177829 Cf. A176983, A177829. %K A177829 nonn %O A177829 1,1 %A A177829 _Zak Seidov_, May 14 2010