login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A003784
Coefficients of Jacobi cusp form of index 1 and weight 10.
2
0, 0, 0, 1, -2, 0, 0, -16, 36, 0, 0, 99, -272, 0, 0, -240, 1056, 0, 0, -253, -1800, 0, 0, 2736, -1464, 0, 0, -4284, 12544, 0, 0, -6816, -19008, 0, 0, 27270, -4554, 0, 0, -6864, 39880, 0, 0, -66013, -26928, 0, 0, 44064, 12544, 0, 0
OFFSET
0,5
REFERENCES
M. Eichler and D. Zagier, The Theory of Jacobi Forms, Birkhauser, 1985, p. 141.
FORMULA
Expansion of eta(4z)^18 * theta_4(z) or (theta_2(z)^12 * theta_3(z)^3 * theta_4(z)^4) / 4096. - Kok Seng Chua (chuaks(AT)ihpc.nus.edu.sg), May 11 2000
Euler transform of period 4 sequence [ -2, -1, -2, -19, ...]. - Michael Somos, Mar 20 2004
Expansion of eta(q)^2 * eta(q^4)^18 / eta(q^2) in powers of q. - Michael Somos, Mar 20 2004
G.f.: x^3 * (Product_{k>0} (1 - x^k) * (1 - x^(4*k))^18 / (1 + x^k)). - Michael Somos, Mar 20 2004
a(4*n + 1) = a(4*n + 2) = 0.
G.f. for a(4*n + 3) = eta(q)^16 * eta(q^2)^5 / eta(q^4)^2; for a(4*n + 4) = -2 * eta(q)^18 * eta(q^4)^2 / eta(q^2). - Michael Somos, Mar 20 2004
EXAMPLE
q^3 - 2*q^4 - 16*q^7 + 36*q^8 + 99*q^11 - 272*q^12 - 240*q^15 + 1056*q^16 + ...
MATHEMATICA
QP = QPochhammer; s = q^3*QP[q]^2*(QP[q^4]^18/QP[q^2]) + O[q]^60; CoefficientList[s, q] (* Jean-François Alcover, Nov 29 2015, adapted from PARI *)
PROG
(PARI) {a(n) = local(A); if( n<3, 0, n-=3; A = x * O(x^n); polcoeff( eta(x + A)^2 * eta(x^4 + A)^18 / eta(x^2 + A), n))} /* Michael Somos, Mar 20 2004 */
CROSSREFS
Cf. A003785.
Sequence in context: A003193 A108474 A120582 * A368849 A244143 A066294
KEYWORD
sign
STATUS
approved