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A007251 McKay-Thompson series of class 5A for the Monster group.
(Formerly M5396)
4
1, 0, 134, 760, 3345, 12256, 39350, 114096, 307060, 776000, 1867170, 4298600, 9540169, 20487360, 42756520, 86967184, 172859325, 336450560, 642489660, 1205572920, 2226005750, 4049168800, 7264172196, 12864273920 (list; graph; refs; listen; history; text; internal format)
OFFSET
-1,3
REFERENCES
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
LINKS
J. H. Conway and S. P. Norton, Monstrous Moonshine, Bull. Lond. Math. Soc. 11 (1979) 308-339.
D. Ford, J. McKay and S. P. Norton, More on replicable functions, Commun. Algebra 22, No. 13, 5175-5193 (1994).
J. McKay and H. Strauss, The q-series of monstrous moonshine and the decomposition of the head characters, Comm. Algebra 18 (1990), no. 1, 253-278.
FORMULA
Expansion of (eta(q) / eta(q^5))^6 + 6 + 125 * (eta(q^5) / eta(q))^6 in powers of q. - Michael Somos, Jul 05 2014
a(n) = A045482(n) = A244745(n) unless n=0.
a(n) ~ exp(4*Pi*sqrt(n/5)) / (sqrt(2)*5^(1/4)*n^(3/4)). - Vaclav Kotesovec, Dec 04 2015
a(n) = A106248(n) + 125*A121591(n) for n > 0. - Seiichi Manyama, Mar 31 2017
EXAMPLE
T5A = 1/q + 134*q + 760*q^2 + 3345*q^3 + 12256*q^4 + 39350*q^5 + ...
MATHEMATICA
a[ n_] := With[ {A = (QPochhammer[ q] / QPochhammer[ q^5])^6 / q}, SeriesCoefficient[ A + 6 + 125 / A, {q, 0, n}]]; (* Michael Somos, Jul 05 2014 *)
PROG
(PARI) {a(n) = my(A); if( n<-1, 0, n++; A = x * O(x^n); A = (eta(x + A) / eta(x^5 + A))^6; polcoeff( A + 6*x + x^2 * 125 / A, n))}; /* Michael Somos, Jul 05 2014 */
CROSSREFS
Sequence in context: A177348 A275997 A370162 * A219443 A348815 A230699
KEYWORD
nonn
AUTHOR
STATUS
approved

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Last modified March 19 01:57 EDT 2024. Contains 370952 sequences. (Running on oeis4.)