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%I #17 Feb 28 2024 18:10:48
%S 1,2,6,52,134,956,4124,20008,73158,439660,1874612,8350808,37583004,
%T 169862616,779948152,3774085968,15435601222,69542934604,329825707332,
%U 1403190752632,6313190864052,29079505547912,126937389732872,552273916408368,2477249228318748
%N Expansion of Product_{n>=1} (1 + (4*x)^n)^(1/2).
%H Seiichi Manyama, <a href="/A298994/b298994.txt">Table of n, a(n) for n = 0..1000</a>
%F Convolution inverse of A298993.
%F a(n) ~ 2^(2*n - 2) * exp(Pi*sqrt(n/6)) / (3^(1/4) * n^(3/4)). - _Vaclav Kotesovec_, Apr 18 2018
%t CoefficientList[Series[Sqrt[QPochhammer[-1, 4*x]/2], {x, 0, 20}], x] (* _Vaclav Kotesovec_, Apr 18 2018 *)
%Y Cf. A298411, A298993, A303074, A370739.
%K nonn
%O 0,2
%A _Seiichi Manyama_, Jan 31 2018