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Theta series of D_20 lattice.
3

%I #12 Oct 16 2018 11:59:54

%S 1,760,77560,2508000,34729720,259114704,1327461600,5341699520,

%T 17701924600,51294999960,131880275664,312126610080,680432137440,

%U 1404010658960,2724593155520,5089580732736,9062110326520,15699349246320,26159307313560,42719885410400,67517852274384

%N Theta series of D_20 lattice.

%D J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer-Verlag, p. 118.

%H Seiichi Manyama, <a href="/A022051/b022051.txt">Table of n, a(n) for n = 0..1000</a>

%t terms = 17; f[q_] = LatticeData["D20", "ThetaSeriesFunction"][-I*Log[q]/Pi]; s = f[q] + O[q]^(2 terms); DeleteCases[CoefficientList[s, q], 0][[1 ;; terms]] (* _Jean-François Alcover_, Jul 06 2017 *)

%K nonn

%O 0,2

%A _N. J. A. Sloane_

%E More terms from _Seiichi Manyama_, Oct 16 2018