OFFSET
0,2
COMMENTS
The convolution square of this sequence is A007263 except for the constant term: T12e(q)^2 = T6d(q^2) - 8. - G. A. Edgar, Apr 17 2017
LINKS
G. C. Greubel, Table of n, a(n) for n = 0..1000 (terms 0..503 from G. A. Edgar)
D. Alexander, C. Cummins, J. McKay and C. Simons, Completely Replicable Functions, LMS Lecture Notes, 165, ed. Liebeck and Saxl (1992), 87-98, annotated and scanned copy.
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^3)^4/eta(q^6)^4 - 4*eta(q^6)^4/eta(q^3)^4) in powers of q. - G. A. Edgar, Apr 17 2017
EXAMPLE
T12f = 1/q -4*q -4*q^5 -16*q^7 +6*q^11 -40*q^13 -8*q^17 +...
MATHEMATICA
eta[q_]:= q^(1/24)*QPochhammer[q]; a[n_]:= SeriesCoefficient[q^(1/2)* (eta[q^3]^4/eta[q^6]^4 - 4*eta[q^6]^4/eta[q^3]^4), {q, 0, n}]; Table[a[n], {n, 0, 50}] (* G. C. Greubel, Jan 25 2018 *)
PROG
(PARI) q='q+O('q^50); A = (eta(q^3)/eta(q^6))^4; Vec(A - 4*q/A) \\ G. C. Greubel, Jun 16 2018
CROSSREFS
KEYWORD
sign
AUTHOR
Michael Somos, Aug 28 2005
STATUS
approved