A289332 Coefficients of (q*(j(q)-1728))^(1/6) where j(q) is the elliptic modular invariant.

1, -164, -34426, -9943880, -3522075375, -1378091288700, -572783373894746, -247966590624315128, -110550043138808626860, -50393645499572805001180, -23374903983625804137812564, -10995211137216964385513242408

Offset: 0

Author

Seiichi Manyama, Jul 02 2017

Keywords

• sign

Crossrefs

(q*(j(q)-1728))^(k/24): A106203 (k=1), A289330 (k=2), A289331 (k=3), this sequence (k=4), A289333 (k=5), A289334 (k=6), A007242 (k=12), A289063 (k=24).

Cf. A289061.

Programs

Mathematica

CoefficientList[Series[((256/QPochhammer[-1, x]^8 + x*QPochhammer[-1, x]^16/256)^3 - 1728*x)^(1/6), {x, 0, 20}], x] (* Vaclav Kotesovec, Mar 07 2018 *)

Formula

G.f.: Product_{k>=1} (1-q^k)^(A289061(k)/6).

a(n) ~ c * exp(2*Pi*n) / n^(4/3), where c = -2^(1/3) * Pi^(1/3) * exp(-Pi/3) / (3^(1/3) * Gamma(2/3) * Gamma(3/4)^(4/3)) = -0.252847812633789641246665071437... - Vaclav Kotesovec, Mar 07 2018