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Expansion of 1/theta_4(q)^3 in powers of q = exp(Pi i t).
4

%I #24 Sep 24 2018 09:40:07

%S 1,6,24,80,234,624,1552,3648,8184,17654,36816,74544,147056,283440,

%T 535008,990912,1803882,3232224,5707624,9943536,17106960,29088352,

%U 48922320,81438528,134261584,219336630,355242288,570675904,909674688,1439394192,2261635168,3529838208

%N Expansion of 1/theta_4(q)^3 in powers of q = exp(Pi i t).

%H Seiichi Manyama, <a href="/A319552/b319552.txt">Table of n, a(n) for n = 0..10000</a>

%F Convolution inverse of A213384.

%F a(n) = (-1)^n * A004404(n).

%F a(0) = 1, a(n) = (6/n)*Sum_{k=1..n} A002131(k)*a(n-k) for n > 0.

%F G.f.: Product_{k>=1} ((1 - x^(2k))/(1 - x^k)^2)^3.

%o (PARI) N=99; x='x+O('x^N); Vec(prod(k=1, N, ((1-x^(2*k))/(1-x^k)^2)^3))

%Y 1/theta_4(q)^b: A015128 (b=1), A001934 (b=2), this sequence (b=3), A284286 (b=4), A319553 (b=8), A319554 (b=12).

%Y Cf. A002131, A002448 (theta_4(q)), A004404, A213384.

%K nonn

%O 0,2

%A _Seiichi Manyama_, Sep 22 2018