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 A136471 #2 Mar 30 2012 18:37:08
%S A136471 1,4,32,756,57008,14053392,11549010240,32284463059856,
%T A136471 312975732247964288,10703164992206736756608,
%U A136471 1309922159165846642159232512,580548577042594102886390324391168
%N A136471 Column 1 of triangle A136470 (scaled): a(n) = A136470(n+1,1)/2^n.
%C A136471 Triangle T = A136470 is defined by: column 0 of T^m = {C(m*2^n, n), n>=0}.
%o A136471 (PARI) {a(n)=local(M=matrix(n+2,n+2,r,c,binomial(r*2^(c-1),c-1)),P); P=matrix(n+2,n+2,r,c,binomial((r+1)*2^(c-1),c-1));(P~*M~^-1)[n+2,2]/2^n}
%Y A136471 Cf. A136470; A136472.
%K A136471 nonn
%O A136471 0,2
%A A136471 _Paul D. Hanna_, Jan 01 2008