A110156 G.f.: A(x) = Product_{n>=1} 1/(1 - 4^n*x^n)^(2/4^n); self-convolution equals A110154.

1, 2, 8, 26, 106, 350, 1512, 5110, 21476, 77886, 319148, 1141038, 4910266, 17499058, 72541048, 272237050, 1121013506, 4112829790, 17377874692, 63697436318, 265450712278, 1003409368250, 4102752994248, 15321419162722, 64725434306768

Offset

0,2

Links

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

Example

A(x) = 1 + 2*x + 8*x^2 + 26*x^3 + 106*x^4 + 350*x^5 +... =
1/[(1-4*x)^(2/4)*(1-16*x^2)^(2/16)*(1-64*x^3)^(2/64)*...].

Prog

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

Crossrefs

Cf. A110152, A110153, A110154, A110155.

Sequence in context: A281345 A348240 A128238 * A295934 A187151 A150674

Adjacent sequences: A110153 A110154 A110155 * A110157 A110158 A110159

Keyword

nonn

Author

Paul D. Hanna, Jul 14 2005

Status

approved