login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A299832
Coefficients in expansion of (q*j(q))^(-1/2) where j(q) is the elliptic modular invariant (A000521).
3
1, -372, 109134, -29582728, 7708451301, -1961287513020, 491099261627462, -121565597132437848, 29833005033279338994, -7271987659286598049924, 1763026435863342757734816, -425536800137353949416343064, 102330765938465480149314691831
OFFSET
0,2
FORMULA
Convolution inverse of A161361.
a(n) ~ (-1)^n * c * exp(Pi*sqrt(3)*n) * sqrt(n), where c = 1.26222636056850175307711547840462898041775779303411175244... = 2^(5/2) * exp(sqrt(3) * Pi/2) * Pi^(11/2) / (3^(3/2) * Gamma(1/3)^9). - Vaclav Kotesovec, Feb 20 2018, updated Mar 06 2018
a(n) * A161361(n) ~ 3*exp(2*sqrt(3)*Pi*n) / (2*Pi*n^2). - Vaclav Kotesovec, Feb 20 2018
MATHEMATICA
CoefficientList[Series[(2 * QPochhammer[-1, x])^12 / (65536 + x*QPochhammer[-1, x]^24)^(3/2), {x, 0, 20}], x] (* Vaclav Kotesovec, Feb 20 2018 *)
CROSSREFS
Sequence in context: A369822 A265659 A238774 * A203439 A265235 A202912
KEYWORD
sign
AUTHOR
Seiichi Manyama, Feb 20 2018
STATUS
approved