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%I #14 Jun 12 2019 20:49:33
%S 1,240,10920,163520,1075860,4464096,14909440,40080000,96643950,
%T 204728400,412819680,754303680,1350075720,2236728480,3673313280,
%U 5666507392,8760753540,12779981760,18827053960,26351976000,37332319752,50483661760,69411962880,91160284800,122167955000
%N Theta series of A_15 lattice.
%D J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer-Verlag, p. 110.
%H G. Nebe and N. J. A. Sloane, <a href="http://www.math.rwth-aachen.de/~Gabriele.Nebe/LATTICES/A15.html">Home page for this lattice</a>
%e 1 + 240*q^2 + 10920*q^4 + 163520*q^6 + 1075860*q^8 + 4464096*q^10 + 14909440*q^12 + 40080000*q^14 + O(q^15)
%t terms = 20; f[q_] = LatticeData["A15", "ThetaSeriesFunction"][-I Log[q]/Pi]; s = Series[f[q], {q, 0, 2 terms}]; CoefficientList[s, q^2][[1 ;; terms]] // Round (* _Jean-François Alcover_, Jul 07 2017 *)
%Y Cf. A023927 (dual).
%K nonn,easy
%O 0,2
%A _N. J. A. Sloane_.
%E More terms from Robert.Harley(AT)inria.fr, see A023902.
%E More terms from _Sean A. Irvine_, Jun 12 2019