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A058509
McKay-Thompson series of class 15B for Monster.
2
1, 0, -1, 4, -3, -2, 11, -6, -11, 20, -15, -16, 43, -24, -32, 76, -48, -58, 144, -84, -97, 238, -144, -172, 398, -234, -279, 636, -372, -428, 1012, -582, -678, 1564, -906, -1028, 2389, -1362, -1576, 3560, -2046, -2320, 5290, -2988, -3407, 7700, -4371, -4928
OFFSET
-1,4
LINKS
D. Ford, J. McKay and S. P. Norton, More on replicable functions, Commun. Algebra 22, No. 13, 5175-5193 (1994).
FORMULA
Expansion of 2 + (eta(q)*eta(q^5)/(eta(q^3)*eta(q^15)))^2 in powers of q. - G. C. Greubel, Jun 14 2018
EXAMPLE
T15B = 1/q - q + 4*q^2 - 3*q^3 - 2*q^4 + 11*q^5 - 6*q^6 - 11*q^7 + 20*q^8 + ...
MATHEMATICA
eta[q_]:= q^(1/24)*QPochhammer[q]; b:= (eta[q]*eta[q^5]/(eta[q^3]* eta[q^15]))^2; a:= CoefficientList[Series[q*(2 + b), {q, 0, 60}], q]; Table[a[[n]], {n, 1, 50}] (* G. C. Greubel, Feb 13 2018 *)
PROG
(PARI) q='q+O('q^50); A = (eta(q)*eta(q^5)/(eta(q^3)*eta(q^15)))^2/q; Vec(2 + A) \\ G. C. Greubel, Jun 14 2018
CROSSREFS
Cf. A093067 (same sequence except for n=0).
Sequence in context: A084483 A266150 A276612 * A105109 A227182 A065367
KEYWORD
sign
AUTHOR
N. J. A. Sloane, Nov 27 2000
EXTENSIONS
More terms from Michel Marcus, Feb 19 2014
STATUS
approved