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A022075 Theta series of D*_22 lattice. 1
1, 0, 44, 0, 924, 0, 12320, 0, 117084, 0, 844536, 4194304, 4812192, 0, 22297792, 92274688, 86075484, 0, 283367436, 968884224, 815677016, 0, 2108077536, 6551502848, 5012882336, 0, 11159625400, 32619102208, 23460347328, 0, 46790491968, 129830486016, 89096422492 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

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 + 44*q^2 + 924*q^4 + ...

PROG

(Sage)

L = [ 1, 0, 44, 0, 924, 0, ]

M = ModularForms(Gamma1(4), 11)

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: A138086 A023933 A271141 * A178986 A174730 A037939

Adjacent sequences:  A022072 A022073 A022074 * A022076 A022077 A022078

KEYWORD

nonn

AUTHOR

N. J. A. Sloane

EXTENSIONS

More terms from Andy Huchala, Jul 14 2021

STATUS

approved

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Last modified September 28 06:40 EDT 2021. Contains 347703 sequences. (Running on oeis4.)