%I #16 Oct 21 2018 13:40:30
%S 1,0,760,0,77560,524288,2508000,10485760,34729720,99614720,259114704,
%T 608174080,1327461600,2739404800,5341699520,9921626112,17701924600,
%U 30592204800,51294999960,83277905920,131880275664
%N Theta series of lattice D20+.
%D J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer-Verlag, p. 120.
%H Seiichi Manyama, <a href="/A014747/b014747.txt">Table of n, a(n) for n = 0..10000</a> (terms 0..2500 from G. C. Greubel)
%F G.f.: (theta2(q)^20 + theta3(q)^20 + theta4(q)^20)/2.
%t terms = 21; s = 1/2 (EllipticTheta[2, 0, q]^20 + EllipticTheta[3, 0, q]^20 + EllipticTheta[4, 0, q]^20) + O[q]^terms; CoefficientList[s, q] (* _Jean-François Alcover_, Jul 07 2017 *)
%Y Cf. A022051.
%K nonn
%O 0,3
%A _N. J. A. Sloane_
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