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 A175484 #2 Mar 30 2012 17:26:34 %S A175484 5,13,9,11,17,13,25,23,37,15,41,17,25,53,21,39,65,33,21,47,77,37,51, %T A175484 23,85,29,27,59,97,45,25,101,27,113,71,121,57,41,133,137,45,33,35,69, %U A175484 157,43,99,73,33,39,181,185,57,85,193,51,119,35,123,93,55,131,217,221,37,45 %N A175484 a(n) = (1/2)*(A175482(n)+A175483(n)). %Y A175484 Cf. A175461, A175482, A175483. %K A175484 nonn %O A175484 1,1 %A A175484 _Zak Seidov_, May 27 2010