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Theta series of laminated lattice LAMBDA_14.
4

%I #8 Jun 19 2021 10:58:43

%S 1,0,1422,13056,84024,285696,958422,2131200,5413374,9655296,20529216,

%T 32221440,61570992,87542784,154925820,206952192,345543480,439022592,

%U 698892510,853288704,1321785360,1557921792,2326595904,2692744704,3941172102,4428518400,6356272428

%N Theta series of laminated lattice LAMBDA_14.

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

%H Andy Huchala, <a href="/A023937/b023937.txt">Table of n, a(n) for n = 0..20000</a>

%o (Sage)

%o e = DirichletGroup(12).1

%o M = ModularForms(e, 7, QQ,prec=30)

%o bases = M.integral_basis()

%o f = sum(x*y for (x,y) in zip(bases,[1, 0, 1422, 13056, 84024, 285696, 958422, 2131200, 5413374, 9655296, 20529216, 32221440, 61570992, 87542784, 154925820, 206952192]))

%o f.coefficients(range(30)) # _Andy Huchala_, Jun 19 2021

%K nonn

%O 0,3

%A _N. J. A. Sloane_.

%E More terms from _Andy Huchala_, Jun 19 2021