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%I #12 Oct 26 2023 00:58:23
%S 1,0,39600,87859200,20779902000,1441891123200,46065617928000,
%T 861717856665600,10894640750334000,102119813013504000,
%U 755967560945968800,4623420024622080000,24151651608982497600,110516220812493619200
%N Theta series of extremal even unimodular lattice in dimension 40.
%D J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer-Verlag, p. 195.
%H Andy Huchala, <a href="/A004671/b004671.txt">Table of n, a(n) for n = 0..20000</a>
%F a(n) = A282015(n) - 1200 * A037945(n) - _Andy Huchala_, May 07 2021
%e G.f.: 1 + 39600*q^2 + 87859200*q^3 + ...
%o (Sage)
%o e4 = eisenstein_series_qexp(4,20,normalization = "integral");
%o delta = CuspForms(1,12).0.q_expansion(20);
%o e4^5-1200*e4^2*delta # _Andy Huchala_, May 07 2021
%K nonn
%O 0,3
%A _N. J. A. Sloane_