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Expansion of eta(q)*eta(q^2)*eta(q^4)*eta(q^8).
5

%I #9 Dec 29 2019 08:41:09

%S 1,-1,-2,1,-1,3,3,-1,-2,-2,4,-4,-1,-3,-3,2,2,8,-3,7,6,-5,-7,0,-3,-2,2,

%T -4,1,-4,1,-2,3,1,7,-6,-3,10,10,5,-7,-3,-4,5,-8,8,-1,-4,-1,-7,-9,2,-3,

%U -6,2,-8,14,5,-6,9,12,4,6,3,8,-14,2,-9,-3,-5,-10,12,6,4,-2,-5,-3,0

%N Expansion of eta(q)*eta(q^2)*eta(q^4)*eta(q^8).

%H G. C. Greubel, <a href="/A030189/b030189.txt">Table of n, a(n) for n = 0..10000</a>

%e G.f. = q^(5/8) - q^(13/8) - 2*q^(21/8) + q^(29/8) - q^(37/8) + ...

%t QP:= QPochhammer; CoefficientList[Series[QP[q]*QP[q^2]*QP[q^4]*QP[q^8], {q, 0, 80}], q] (* _G. C. Greubel_, Dec 28 2019 *)

%o (PARI) my(x='x+O('x^80)); Vec(eta(x)*eta(x^2)*eta(x^4)*eta(x^8)) \\ _G. C. Greubel_, Dec 28 2019

%K sign

%O 0,3

%A _N. J. A. Sloane_