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 A015232 #8 Jul 24 2021 02:30:06 %S A015232 1,0,276,888,3564,8136,16908,30456,58380,74256,145800,186048,265866, %T A015232 363528,555384,576000,939924,1063800,1355820,1659528,2302704,2206848, %U A015232 3387744,3557664,4263468,4961736,6611736,6043416,8841960,9005112,10439424,11761848,15056124 %N A015232 Theta series of lattice Kappa_10. %D A015232 J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer-Verlag, p. 161. %H A015232 Andy Huchala, <a href="/A015232/b015232.txt">Table of n, a(n) for n = 0..20000</a> %e A015232 G.f. = 1 + 276*q^4 + 888*q^6 + ... %o A015232 (Sage) %o A015232 L = [ 1, 0, 276, 888, 3564, 8136, 16908, 30456, 58380, 74256, 145800, 186048, 265866, 363528, 555384, 576000] %o A015232 e = DirichletGroup(18,QQ).0 %o A015232 M = ModularForms(e, 5) %o A015232 bases = [_.q_expansion(40) for _ in M.integral_basis()] %o A015232 f = sum(x*y for (x, y) in zip(bases, L)); list(f) # _Andy Huchala_, Jul 23 2021 %K A015232 nonn %O A015232 0,3 %A A015232 _N. J. A. Sloane_ %E A015232 More terms from _Andy Huchala_, Jul 23 2021