OFFSET
0,2
COMMENTS
The convolution square of this sequence is A121667: T12G(q)^2 = T6D(q^2). - G. A. Edgar, Apr 15 2017
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..1000 (terms 0..502 from G. A. Edgar)
D. Ford, J. McKay and S. P. Norton, More on replicable functions, Commun. Algebra 22, No. 13, 5175-5193 (1994).
FORMULA
Expansion of q^(1/2)*(eta(q)*eta(q^2)/(eta(q^3)*eta(q^6)))^2 in powers of q. - G. C. Greubel, Jun 18 2018
EXAMPLE
T12G = 1/q - 2*q - 3*q^3 + 8*q^5 - 2*q^7 - 6*q^9 + 18*q^11 - 20*q^13 - ...
MATHEMATICA
eta[q_]:= q^(1/24)*QPochhammer[q]; a:= CoefficientList[Series[q^(1/2) (eta[q]*eta[q^2]/(eta[q^3]*eta[q^6]))^2, {q, 0, 60}], q]; Table[a[[n]], {n, 0, 50}] (* G. C. Greubel, Jun 18 2018 *)
PROG
(PARI) q='q+O('q^50); Vec((eta(q)*eta(q^2)/(eta(q^3)*eta(q^6)))^2) \\ G. C. Greubel, Jun 18 2018
CROSSREFS
KEYWORD
sign
AUTHOR
N. J. A. Sloane, Nov 27 2000
STATUS
approved