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%I #11 Apr 25 2018 06:05:34
%S 1,-2,-6,-116,-7914,-2080044,-2143234268,-8791784539464,
%T -144097582730402202,-9444444682320960008908,
%U -2475861188239098437867827380,-2596143477450571483513272599120280,-10889030549158315918778789768740624543108
%N Expansion of Product_{k>=1} ((1 - (2^k*x)^k)/(1 + (2^k*x)^k))^(1/2^k).
%H Seiichi Manyama, <a href="/A303441/b303441.txt">Table of n, a(n) for n = 0..58</a>
%F a(n) ~ -2^(n^2 - n + 1). - _Vaclav Kotesovec_, Apr 25 2018
%o (PARI) N=20; x='x+O('x^N); Vec(prod(k=1, N, ((1-(2^k*x)^k)/(1+(2^k*x)^k))^(1/2^k)))
%Y Cf. A303306, A303394, A303395, A303440.
%K sign
%O 0,2
%A _Seiichi Manyama_, Apr 24 2018