A022073 Theta series of D*_20 lattice.

1, 40, 760, 9120, 77560, 1546224, 2508000, 31204160, 34729720, 300136200, 259114704, 1823305440, 1327461600, 8216920880, 5341699520, 29758804416, 17701924600, 91800254160, 51294999960, 249835104800, 131880275664, 614963569920, 312126610080, 1394448792000

Offset

0,2

References

J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer-Verlag, p. 120.

Links

Andy Huchala, Table of n, a(n) for n = 0..20000

Example

G.f. = 1 + 40*q^2 + 760*q^4 + ...

Prog

(Sage)
L = [ 1, 40, 760]
M = ModularForms(Gamma0(2), 10)
bases = [_.q_expansion(20) for _ in M.integral_basis()]
f = sum(x*y for (x, y) in zip(bases, L)); list(f) # Andy Huchala, Jul 14 2021

Crossrefs

Sequence in context: A233725 A175603 A319308 * A261571 A010956 A006240

Adjacent sequences: A022070 A022071 A022072 * A022074 A022075 A022076

Keyword

nonn

Author

N. J. A. Sloane

Extensions

More terms from Andy Huchala, Jul 14 2021

Status

approved