cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A299830 Coefficients in expansion of (q*j(q))^(-1/4) where j(q) is the elliptic modular invariant (A000521).

Original entry on oeis.org

1, -186, 37269, -7859330, 1697901090, -371924784000, 82208011242071, -18286478726628018, 4086893434159800000, -916721490080116189690, 206224024157150867919738, -46501365201275569893140034, 10506135153567544547655979849
Offset: 0

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Author

Seiichi Manyama, Feb 20 2018

Keywords

Crossrefs

Programs

  • Mathematica
    CoefficientList[Series[(2 * QPochhammer[-1, x])^6 / (65536 + x*QPochhammer[-1, x]^24)^(3/4), {x, 0, 20}], x] (* Vaclav Kotesovec, Feb 20 2018 *)

Formula

Convolution inverse of A289301.
a(n) ~ (-1)^n * c * exp(Pi*sqrt(3)*n) / n^(1/4), where c = 0.863092410616421890391706584312871736447175709008670875907... = 2^(1/4) * exp(sqrt(3) * Pi/4) * Pi^2 * Gamma(1/4) / (3^(3/4) * Gamma(1/3)^(9/2)). - Vaclav Kotesovec, Feb 20 2018, updated Mar 06 2018
a(n) * A289301(n) ~ -3*exp(2*sqrt(3)*Pi*n) / (2^(5/2)*Pi*n^2). - Vaclav Kotesovec, Feb 20 2018