OFFSET
1,1
REFERENCES
J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer-Verlag.
LINKS
G. C. Greubel, Table of n, a(n) for n = 1..1000
G. Nebe and N. J. A. Sloane, Home page for odd Leech lattice
E. M. Rains and N. J. A. Sloane, The Shadow Theory of Modular and Unimodular Lattices, J. Number Theory, 73 (1998), 359-389.
FORMULA
G.f.: (1/16)*( theta2(z)^24 + 3*theta4(2*z)^8 * theta2(z)^16 + (3/16)*theta4(2*z)^16 * theta2(z)^8 ).
MATHEMATICA
CoefficientList[Series[(EllipticTheta[2, 0, q^(1/2)]^24 + 3*EllipticTheta[2, 0, q^(1/2)]^16*EllipticTheta[4, 0, q]^8 + (3/16)*EllipticTheta[2, 0, q^(1/2)]^8*EllipticTheta[4, 0, q]^16)/16, {q, 0, 30}], q] (* G. C. Greubel, Mar 15 2022 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Kok Seng Chua (chuaks(AT)ihpc.nus.edu.sg), Jun 22 2000
STATUS
approved