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 A029897 #10 Jul 24 2021 01:08:31 %S A029897 1,0,918,6624,36450,120096,322436,764640,1637766,2912544,5591592, %T A029897 9160992,14668002,22913280,35544420,48529440,74114514,100230912, %U A029897 136486530,184801824,252809100,308852640,426995388,528491520,664053284,836215488,1070501400,1229873472 %N A029897 Theta series of 13-dimensional lattice Kappa_13 with minimal norm 4. %D A029897 J. H. Conway and N. J. A. Sloane, "Sphere Packings, Lattices and Groups", Springer-Verlag, p. 161. %H A029897 Andy Huchala, <a href="/A029897/b029897.txt">Table of n, a(n) for n = 0..1000</a> %H A029897 G. Nebe and N. J. A. Sloane, <a href="http://www.math.rwth-aachen.de/~Gabriele.Nebe/LATTICES/KAPPA13.html">Home page for this lattice</a> %e A029897 G.f. = 1 + 918*q^4 + 6624*q^6 + ... %o A029897 (Magma) %o A029897 L := (Lattice("Kappa", 13)); %o A029897 B := Basis(ThetaSeriesModularFormSpace(L), 55); %o A029897 S := [1, 0, 918, 6624, 36450, 120096, 322436, 764640, 1637766, 2912544, 5591592, 9160992, 14668002, 22913280, 35544420, 48529440, 74114514, 100230912, 136486530, 184801824, 252809100, 308852640, 426995388, 528491520, 664053284]; %o A029897 Coefficients(&+[B[i] * S[i] : i in [1..25]]); // _Andy Huchala_, Jul 23 2021 %K A029897 nonn %O A029897 0,3 %A A029897 _N. J. A. Sloane_ %E A029897 More terms from _Andy Huchala_, Jul 23 2021