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 A024856 #3 Mar 30 2012 18:56:00 %S A024856 0,1,3,2,4,3,6,9,13,12,17,16,21,19,25,32,40,39,47,45,54,52,62,60,71, %T A024856 82,94,92,105,103,117,115,130,127,142,139,155,172,190,188,207,205,224, %U A024856 221,241,238,259,256,278,275,298,322,346,343,368,365,391,388,415,412,440,437,466 %N A024856 a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (natural numbers), t = A023532. %K A024856 nonn %O A024856 2,3 %A A024856 _Clark Kimberling_