This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A004670 #32 Jul 06 2021 20:18:25 %S A004670 1,0,146880,64757760,4844836800,137695887360,2121555283200, %T A004670 21421110804480,158757684004800,928986331545600,4512164186816640, %U A004670 18847854517248000,69519016873985280,230952108679004160 %N A004670 Theta series of extremal even unimodular lattice in dimension 32. %C A004670 There are at least 15 such lattices, one of which is the Barnes-Wall lattice BW_32. %D A004670 J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer-Verlag, p. 195. %H A004670 Andy Huchala, <a href="/A004670/b004670.txt">Table of n, a(n) for n = 0..20000</a> %H A004670 N. Elkies, <a href="http://people.math.harvard.edu/~elkies/M272.19/nov04.pdf">Rational Lattices and their Theta Functions</a> %H A004670 N. Heninger, E. M. Rains and N. J. A. Sloane, <a href="https://arxiv.org/abs/math/0509316">On the Integrality of n-th Roots of Generating Functions</a>, arXiv:math/0509316 [math.NT], 2005-2006; J. Combinatorial Theory, Series A, 113 (2006), 1732-1745. %H A004670 G. Nebe and N. J. A. Sloane, <a href="http://www.math.rwth-aachen.de/~Gabriele.Nebe/LATTICES/KV32RM.html">Home page for this lattice</a> %H A004670 <a href="/index/Ba#BW">Index entries for sequences related to Barnes-Wall lattices</a> %F A004670 a(n) = A282012(n) - 960*A027364(n-1) for n > 0. - _Andy Huchala_, May 01 2021 %e A004670 G.f.: 1 + 146880*q^2 + 64757760*q^3 + 4844836800*q^4 + ... %o A004670 (Sage) %o A004670 e4 = eisenstein_series_qexp(4,20,normalization = "integral"); %o A004670 delta = CuspForms(1,12).0.q_expansion(20); %o A004670 (e4^4 - 960*delta*e4).list()[:20] # _Andy Huchala_, May 01 2021 %Y A004670 Cf. A027364, A282012. %K A004670 nonn %O A004670 0,3 %A A004670 _N. J. A. Sloane_