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%I #4 Oct 30 2017 18:00:35
%S 1,-1,1,0,-2,3,-2,-1,6,-10,8,2,-19,34,-30,-3,60,-112,106,-2,-188,370,
%T -373,48,586,-1226,1307,-296,-1808,4046,-4546,1430,5516,-13300,15724,
%U -6217,-16626,43566,-54132,25464,49373,-142146,185496,-100306,-143896,461874,-632864,384348,409270,-1494356,2150240
%N Expansion of 1/(1 + Sum_{i>=1} q^(i^2)/Product_{j=1..i} (1 + q^(2*j))).
%C Convolution inverse of the 3rd order mock theta function phi(q) (A053250).
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/MockThetaFunction.html">Mock Theta Function</a>
%F G.f.: 1/(1 + Sum_{i>=1} q^(i^2)/Product_{j=1..i} (1 + q^(2*j))).
%t nmax = 50; CoefficientList[Series[1/(1 + Sum[q^(i^2)/Product[1 + q^(2 j), {j, 1, i}], {i, 1, nmax}]), {q, 0, nmax}], q]
%Y Cf. A053250, A081360, A294407.
%K sign
%O 0,5
%A _Ilya Gutkovskiy_, Oct 30 2017