A137157 G.f.: 1 = Sum_{n>=0} a(n)*x^n/(1+x)^(2*2^n).

1, 2, 5, 24, 239, 4920, 206727, 17568408, 3003763243, 1030272816360, 707851744149198, 973425618916674288, 2678332881795756783639, 14741522294008025924154864, 162290544340043699103996962253, 3573515596966915773419766367302288, 157376160486791180710467411977740266927

Offset: 0

Author

Paul D. Hanna, Jan 24 2008

Keywords

• nonn

Comments

Equals unsigned column 1 of triangle A137156.

Crossrefs

Cf. A137156; A001192, A137158, A137159, A137160.

Programs

PARI

{a(n)=polcoeff(1-sum(k=0, n-1, a(k)*x^k/(1+x+x*O(x^n))^(2^(k+1)) ), n)}

Extensions

a(15)-a(16) from Alois P. Heinz, Jan 04 2023