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A136560 McKay-Thompson series of class 49a for the Monster group with a(0) = 3. 0
1, 3, 2, 1, 2, 3, 4, 5, 7, 8, 11, 13, 16, 19, 25, 28, 35, 41, 50, 58, 71, 81, 98, 113, 134, 154, 183, 208, 244, 280, 326, 371, 431, 489, 565, 641, 735, 832, 953, 1075, 1225, 1382, 1569, 1764, 1999, 2243, 2533, 2839, 3195, 3575, 4018, 4484, 5026, 5604, 6267, 6975 (list; graph; refs; listen; history; internal format)
OFFSET

-1,2

COMMENTS

Denoted 49Z in Conway+Norton with a slight typo in the formula on page 337.

REFERENCES

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).

LINKS

Index entries for McKay-Thompson series for Monster simple group

FORMULA

Expansion of ( eta(q^4)^4 + 7 * eta(q)^2 * eta(q^49)^2 ) / ( eta(q) * eta(q^49) * ( eta(q)^2 + 7 * eta(q) * eta(q^49) + 7 * eta(q^49)^2 ) ) in powers of q.

EXAMPLE

1/q + 3 + 2*q + q^2 + 2*q^3 + 3*q^4 + 4*q^5 + 5*q^6 + 7*q^7 + 8*q^8 + ...

PROG

(PARI) {a(n) = local(A, A1, A2, A3); if( n<-1, 0, n++; A = x * O(x^n); A1 = eta(x + A); A2 = eta(x^7 + A); A3 = eta(x^49 + A); polcoeff( (A2^4 + 7 * x^3 * A1^2 * A3^2) / (A1 * A3) / (A1^2 + 7 * x^2 * A1*A3 + 7 * x^4 * A3^2 ), n))}

CROSSREFS

Cf. A058700(n) = a(n) unless n=0.

Sequence in context: A047878 A120441 A183041 * A105847 A048984 A136531

Adjacent sequences:  A136557 A136558 A136559 * A136561 A136562 A136563

KEYWORD

nonn

AUTHOR

Michael Somos, Jan 05 2008

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Last modified February 17 14:46 EST 2012. Contains 206047 sequences.