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 A024887 #3 Mar 30 2012 18:56:00 %S A024887 0,0,4,6,8,9,11,12,23,27,29,33,37,39,43,46,65,70,74,80,84,89,94,98, %T A024887 104,109,137,143,150,157,163,169,176,183,189,195,202,209,248,256,265, %U A024887 272,281,289,296,306,313,321,329,337,346,354,406,416,425,436,445,454,466,474,484,493 %N A024887 a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = A023531, t = A000201 (lower Wythoff sequence). %K A024887 nonn %O A024887 2,3 %A A024887 _Clark Kimberling_