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A022073 Theta series of D*_20 lattice. 1
1, 40, 760, 9120, 77560, 1546224, 2508000, 31204160, 34729720, 300136200, 259114704, 1823305440, 1327461600, 8216920880, 5341699520, 29758804416, 17701924600, 91800254160, 51294999960, 249835104800, 131880275664, 614963569920, 312126610080, 1394448792000 (list; graph; refs; listen; history; text; internal format)
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

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Last modified October 24 09:09 EDT 2021. Contains 348220 sequences. (Running on oeis4.)