A303442 Expansion of Product_{k>=1} ((1 + 4^k*x^k)/(1 - 4^k*x^k))^(1/4^k).

1, 2, 4, 18, 34, 166, 544, 2222, 5396, 29622, 101276, 411206, 1170986, 5435466, 20007472, 90854146, 253956882, 1160301990, 4412414972, 18080729238, 56012061494, 275783908498, 1010620487696, 4103148863306, 12730394683264, 58227896627114, 223877604671508

Offset: 0

Author

Seiichi Manyama, Apr 24 2018

Keywords

• nonn

Links

• Seiichi Manyama, Table of n, a(n) for n = 0..1000

Crossrefs

Cf. A303361, A303438, A303443.

Programs

Mathematica

nmax = 30; CoefficientList[Series[Exp[Sum[((-1)^j - 1) / (j*(1 - 1/(4^(j-1)*x^j))), {j, 1, nmax}]], {x, 0, nmax}], x] (* Vaclav Kotesovec, Apr 25 2018 *)

PARI

N=66; x='x+O('x^N); Vec(prod(k=1, N, ((1+4^k*x^k)/(1-4^k*x^k))^(1/4^k)))