A136472 Column 2 of triangle A136470 (scaled): a(n) = A136470(n+2,2)/4^n.

1, 8, 136, 6552, 973832, 465833856, 739387804752, 3992649623654752, 74888425049167499424, 4962998789388515787006336, 1178375010889854741001146703936, 1013755301703927988518902015091910656

Offset: 0

Author

Paul D. Hanna, Jan 01 2008

Keywords

• nonn

Comments

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

Crossrefs

Cf. A136470; A136471.

Programs

PARI

{a(n)=local(M=matrix(n+3,n+3,r,c,binomial(r*2^(c-1),c-1)),P); P=matrix(n+3,n+3,r,c,binomial((r+1)*2^(c-1),c-1));(P~*M~^-1)[n+3,3]/4^n}