A023940 Theta series of laminated lattice LAMBDA_18.

1, 0, 7398, 175104, 1820448, 10506240, 46589382, 155022336, 465542694, 1157492736, 2774172672, 5765465088, 11929117248, 21932052480, 40953956940, 68918860800, 119138987808, 187615014912, 305761893030, 456635833344, 710329749696, 1017103417344, 1522382017536

Offset

0,3

References

J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer-Verlag, p. 174.

Links

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

Prog

(Sage)
e = DirichletGroup(6).0
M = ModularForms(e, 9, QQ)
bases = [_.q_expansion(30) for _ in M.integral_basis()]
list(sum(x*y for (x, y) in zip(bases, [1, 0, 7398, 175104, 1820448, 10506240, 46589382, 155022336, 465542694, 1157492736]))) # Andy Huchala, Jun 17 2021

Crossrefs

Sequence in context: A034279 A031584 A237311 * A116195 A249878 A360328

Adjacent sequences: A023937 A023938 A023939 * A023941 A023942 A023943

Keyword

nonn

Author

N. J. A. Sloane.

Extensions

More terms from Andy Huchala, Jun 17 2021

Status

approved