OFFSET
0,3
COMMENTS
Theta series is an element of the space of modular forms on Gamma_1(48) with Kronecker character 12 in modulus 48, weight 17/2, and dimension 66 over the integers.
REFERENCES
J. H. Conway and N. J. A. Sloane, Sphere Packings, Lattices and Groups, Chap. 6.
LINKS
G. Nebe and N. J. A. Sloane, Home page for this lattice.
EXAMPLE
G.f. = 1 + 4266*q^4 + 81792*q^6 + ...
PROG
(Magma)
prec := 10;
S := SymmetricMatrix([4, 2, 4, 0, -2, 4, 0, -2, 0, 4, 0, 0, -2, 0, 4, -2, -2, 0, 0, 0, 4, -2, -1, 1, 0, 0, 0, 4, -2, -1, 0, -1, 1, 2, 2, 4, -2, -2, 0, 1, 1, 2, 2, 2, 4, -2, 0, -2, 0, 1, 1, 0, 0, 0, 4, 1, 1, 0, 0, 0, -2, 0, -1, -1, -2, 4, -2, -1, 0, 0, 0, 1, 1, 1, 1, 1, -2, 4, 0, -1, 1, 1, 0, -1, 1, 0, 0, -1, 1, -1, 4, 0, 0, 0, 0, 0, 0, 1, 0, 1, -1, 1, -1, 1, 4, 0, 0, 0, 0, -1, 1, -1, 0, 0, 0, -1, 0, 0, -1, 4, -1, 0, 0, -1, 0, 0, 0, 0, 0, 1, -1, 1, 0, 0, -1, 4, 0, 0, 0, 0, 0, 0, 0, 1, 0, -1, 1, -1, 1, 0, 1, -1, 4]);
L := LatticeWithGram(S);
T<q> := ThetaSeries(L, 2*prec);
[Coefficients(T)[2*i-1] : i in [1..prec]];
CROSSREFS
KEYWORD
nonn
AUTHOR
Andy Huchala, May 07 2023
STATUS
approved