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A029696
Theta series of 7-dimensional lattice Kappa_7*.
1
1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 22, 0, 0, 64, 0, 0, 0, 0, 40, 0, 0, 64, 44, 0, 0, 0, 0, 0, 0, 0, 80, 0, 0, 0, 240, 0, 0, 448, 0, 0, 0, 0, 112, 0, 0, 384, 480, 0, 0, 0, 0, 0, 0, 0, 220, 0, 0, 0, 450, 0, 0, 1408, 0, 0, 0, 0, 480, 0, 0, 960, 812
OFFSET
0,13
REFERENCES
J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer-Verlag, p. 161.
LINKS
Sean A. Irvine, Java program (github)
G. Nebe and N. J. A. Sloane, Home page for this lattice
EXAMPLE
G.f. = 1 + 2*q^12 + 22*q^16 + ...
PROG
(Magma)
L := Dual(Lattice("Kappa", 7));
B := Basis(ThetaSeriesModularFormSpace(L), 100);
S := [1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 2, 0, 0, 0, 22, 0, 0, 64, 0, 0, 0, 0, 40, 64];
Coefficients(&+[B[i] * S[i] : i in [1..26]]); // Andy Huchala, Jul 24 2021
CROSSREFS
Cf. A015236.
Sequence in context: A342376 A277443 A209401 * A118887 A372353 A372359
KEYWORD
nonn
EXTENSIONS
More terms from Sean A. Irvine, Mar 02 2020
STATUS
approved