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
EXAMPLE
G.f.: 1 + 10668*q^4 + 317952*q^6 + 3747430*q^8 + 24569856*q^10 + 117503960*q^12 + ...
PROG
(Magma) L:=Lattice("Lambda", 19); T<q> := ThetaSeries(L, 12); T;
(Magma)
L := Lattice("Lambda", 19);
B := Basis(ThetaSeriesModularFormSpace(L), 30);
S := [1, 0, 10668, 317952, 3747430, 24569856, 117503960, 428990464, 1355705388, 3631734784, 9033649880, 19996626432, 42549627976, 82713667584, 157758704304, 279165280256, 490745951846, 808950325248, 1335670719108, 2081937198592];
Coefficients(&+[B[i] * S[i] : i in [1..20]]); // Andy Huchala, Jun 17 2021
CROSSREFS
KEYWORD
nonn
AUTHOR
EXTENSIONS
More terms from Andy Huchala, Jun 17 2021
STATUS
approved