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 A126887 #7 Sep 05 2019 11:09:27 %S A126887 5,13,17,25,26,29,43,50,58,61,65,67,73,77,85,86,93,101,103,109,111, %T A126887 116,122,130,133,134,137,145,146,149,155,163,170,172,173,181,183,186, %U A126887 193,197,202,206,218,233,235,237,241,245,259,260,266,267,268,273,277,281 %N A126887 a(n) = A005278(n)/2. %Y A126887 Cf. A005278. %K A126887 nonn %O A126887 1,1 %A A126887 _Artur Jasinski_, Dec 30 2006 %E A126887 More terms from _Amiram Eldar_, Sep 05 2019