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 A362876 #17 May 10 2023 05:19:04 %S A362876 1,0,2772,42624,335052,1545984,5698860,16297344,42785244,94440960, %T A362876 204094296,385391232,730053060,1240934400,2151268128,3374469504, %U A362876 5476016700,8115545088,12477938100,17677480320,26111897640,35570481408,50909418000,67336722432,93433877268 %N A362876 Theta series of 16-dimensional lattice Kappa_16. %C A362876 Theta series is an element of the space of modular forms on Gamma_0(12) of weight 8 and dimension 17 over the integers. %D A362876 J. H. Conway and N. J. A. Sloane, Sphere Packings, Lattices and Groups, Chap. 6. %H A362876 Andy Huchala, <a href="/A362876/b362876.txt">Table of n, a(n) for n = 0..20000</a> %H A362876 G. Nebe and N. J. A. Sloane, <a href="http://www.math.rwth-aachen.de/~Gabriele.Nebe/LATTICES/KAPPA16.1.html">Home page for this lattice</a>. %e A362876 G.f. = 1 + 2772*q^4 + 42624*q^6 + ... %o A362876 (Magma) %o A362876 prec := 40; %o A362876 S := SymmetricMatrix([4,2,4,0,-2,4,0,-2,0,4,0,0,-2,0,4,-2,-2,0,0,0,4,-2,-1,1,0,0,0,4,-2,-1,0,-1,1,2,2,4,-2,-2,0,1,1,2,2,2,4,-2,0,-2,0,1,1,0,0,0,4,1,1,0,0,0,-2,0,-1,-1,-2,4,-2,-1,0,0,0,1,1,1,1,1,-2,4,0,-1,1,1,0,-1,1,0,0,-1,1,-1,4,0,0,0,0,0,0,1,0,1,-1,1,-1,1,4,0,0,0,0,-1,1,-1,0,0,0,-1,0,0,-1,4,-1,0,0,-1,0,0,0,0,0,1,-1,1,0,0,-1,4]); %o A362876 L := LatticeWithGram(S); %o A362876 T<q> := ThetaSeries(L, 32); %o A362876 M := ThetaSeriesModularFormSpace(L); %o A362876 B := Basis(M,prec); %o A362876 Coefficients(&+[Coefficients(T)[2*i-1]*B[i] : i in [1..17]]); %Y A362876 Cf. A029897, A047628, A362875, A362877, A362878, A362879, A362880. %K A362876 nonn %O A362876 0,3 %A A362876 _Andy Huchala_, May 07 2023