A136471 - OEIS

%I #2 Mar 30 2012 18:37:08

%S 1,4,32,756,57008,14053392,11549010240,32284463059856,

%T 312975732247964288,10703164992206736756608,

%U 1309922159165846642159232512,580548577042594102886390324391168

%N Column 1 of triangle A136470 (scaled): a(n) = A136470(n+1,1)/2^n.

%C Triangle T = A136470 is defined by: column 0 of T^m = {C(m*2^n, n), n>=0}.

%o (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 Cf. A136470; A136472.

%K nonn

%O 0,2

%A _Paul D. Hanna_, Jan 01 2008