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A000706 Expansion of modular function 1/E_3 (cf. A013973).
(Formerly M5458 N2367)
0
1, 504, 270648, 144912096, 77599626552, 41553943041744, 22251789971649504, 11915647845248387520, 6380729991419236488504, 3416827666558895485479576, 1829682703808504464920468048, 979779820147442370107345764512 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

REFERENCES

G. H. Hardy and S. Ramanujan, On the coefficients in the expansion of certain modular functions, Proc. Royal Soc., A95 (1918), 144-155 [G. H. Hardy, Coll. Papers, Vol. 1, 294-305.] - Added by N. J. A. Sloane, Feb 21 2010.

S. Ramanujan, Collected Papers of Srinivasa Ramanujan, pp. 115-7, Ed. G. H. Hardy et al., AMS Chelsea 2000, p. 317.

N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

FORMULA

Expansion of Ramanujan's function 1/R(q) in powers of q.

G.f. A(x) satisfies 0= f(A(x), A(x^2), A(x^4)) where f(u, v, w)= v^2*w^2 +121*u^2*w^2 +4096*u^2*v^2 -8*v^3*w -512*u*v^3 -66*u*v*w^2 +592*u*v^2*w -4224*u^2*v*w. - Michael Somos Aug 09 2007

PROG

(PARI) {a(n)= if(n<0, 0, polcoeff( 1/sum(k=1, n, -504*sigma(k, 5)*x^k, 1+x*O(x^n)), n))} /* Michael Somos Aug 09 2007 */

CROSSREFS

Convolution inverse of A013973.

Sequence in context: A145095 A035293 A105097 * A068299 A003798 A003791

Adjacent sequences:  A000703 A000704 A000705 * A000707 A000708 A000709

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com).

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Last modified February 17 19:13 EST 2012. Contains 206085 sequences.