A099606 Row sums of triangle A099605, in which row n equals the inverse Binomial transform of column n of the triangle A034870 of even-indexed rows of Pascal's triangle.

1, 4, 10, 48, 116, 560, 1352, 6528, 15760, 76096, 183712, 887040, 2141504, 10340096, 24963200, 120532992, 290992384, 1405035520, 3392055808, 16378294272, 39540700160, 190919389184, 460920178688, 2225519493120, 5372879343616

Offset

0,2

Links

Table of n, a(n) for n=0..24.

Index entries for linear recurrences with constant coefficients, signature (0, 12, 0, -4).

Formula

a(n) = Pell(n+1)*2^[(n+1)/2]. a(n) = 12*a(n-2) - 4*a(n-4) for n>=4. G.f.: (1+4*x-2*x^2)/(1-12*x^2+4*x^4).

Example

Sequence begins: {1*1, 2*2, 5*2, 12*4, 29*4, 70*8, 169*8, 408*16, ...}.

Prog

(PARI) a(n)=polcoeff((1+4*x-2*x^2)/(1-12*x^2+4*x^4)+x*O(x^n), n)

Crossrefs

Cf. A099603, A099605, A034870, A000129.

Sequence in context: A115327 A233395 A197664 * A149231 A335873 A364281

Adjacent sequences: A099603 A099604 A099605 * A099607 A099608 A099609

Keyword

nonn

Author

Paul D. Hanna, Oct 25 2004

Status

approved