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A058548 McKay-Thompson series of class 18j for Monster. 0
1, 0, 1, -2, 0, 2, 1, 0, 3, 2, 0, 2, -4, 0, 1, 0, 0, 2, 7, 0, 4, -10, 0, 8, 3, 0, 8, 10, 0, 8, -15, 0, 7, 2, 0, 10, 22, 0, 17, -32, 0, 22, 10, 0, 26, 32, 0, 24, -48, 0, 25, 8, 0, 30, 62, 0, 43, -88, 0, 58, 22, 0, 65, 88, 0, 66, -127, 0, 66, 22, 0, 80, 152, 0, 107, -214, 0, 136, 52, 0 (list; graph; refs; listen; history; internal format)
OFFSET

-1,4

COMMENTS

G.f. A(x) satisfies 0=f(A(x),A(x^2))=f(A(x),A(-x)) where f(u,v)= 32+4(u+v)-2(u^2+v^2)+2(u^3+v^3)-3uv(u+v)+(u^4+v^4)+uv(u^2+v^2)-(uv)^2(u+v). - Michael Somos Apr 20 2004

REFERENCES

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

a(3n)=0.

EXAMPLE

T18j = 1/q + q - 2*q^2 + 2*q^4 + q^5 + 3*q^7 + 2*q^8 + 2*q^10 - 4*q^11 + ...

PROG

(PARI) a(n)=local(A); if(n<0, n==-1, A=x^2*O(x^n); A=((eta(x^3+A)*eta(x^18+A)^2*eta(x^27+A))/(eta(x^6+A)*eta(x^9+A)^2*eta(x^54+A)))^2/x; polcoeff(A+1/A, n)) /* Michael Somos Apr 20 2004 */

CROSSREFS

Cf. A000521, A007240, A014708, A007241, A007267, A045478, etc.

Sequence in context: A097364 A177446 A074905 * A157030 A080844 A076626

Adjacent sequences:  A058545 A058546 A058547 * A058549 A058550 A058551

KEYWORD

sign

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com), Nov 27, 2000

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Last modified February 14 23:53 EST 2012. Contains 205689 sequences.