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%I #15 Apr 28 2018 09:41:18
%S 1,-2,0,-10,22,-102,84,-950,3360,-18006,21968,-162126,613830,-2772010,
%T 3847740,-38669210,145735622,-567469350,901506480,-6688787966,
%U 27166965906,-137118406226,234942672620,-1425038557410,6527750118052,-27227710098826
%N Expansion of Product_{k>=1} ((1 - 4^k*x^k)/(1 + 4^k*x^k))^(1/4^k).
%H Seiichi Manyama, <a href="/A303490/b303490.txt">Table of n, a(n) for n = 0..1000</a>
%F G.f.: exp(Sum_{j>=1} ((1 - (-1)^j) / (j*(1 - 1/(4^(j-1)*x^j))) )). - _Vaclav Kotesovec_, Apr 25 2018
%t nmax = 30; CoefficientList[Series[Exp[Sum[(1 - (-1)^j) / (j*(1 - 1/(4^(j-1)*x^j))), {j, 1, nmax}]], {x, 0, nmax}], x] (* _Vaclav Kotesovec_, Apr 25 2018 *)
%o (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)))
%Y Cf. A303394, A303439, A303442, A303491.
%K sign
%O 0,2
%A _Seiichi Manyama_, Apr 24 2018
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