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 A152560 #3 Mar 30 2012 18:37:15 %S A152560 1,1,3,7,37,225,2707,47991,1566965,85002865,8346008131,1441358958439, %T A152560 452666387604933,257384373709193473,268828878795481175283, %U A152560 516988085848458847554135,1844678455777198460320221077 %N A152560 a(n) = A131205(A005578(n)). %C A152560 Related to binary partitions (A000123); A131205 is defined by a(n) = a(n-1) + a(floor(n/2)) + a(ceiling(n/2)) and A005578(n) = (2^(n+1)+3+(-1)^n)/6. %o A152560 (PARI) {a(n)=local(N=(2^(n+1)+3+(-1)^n)/6,X=x+O(x^N));polcoeff(1/((1-X)^2*prod(m=0,n-1,1-X^(2^m))),N-1)} %Y A152560 Cf. A131205, A005578, A000123. %K A152560 nonn %O A152560 0,3 %A A152560 _Paul D. Hanna_, Dec 22 2008