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 A089799 #15 Feb 16 2025 08:32:51
%S A089799 2,2,0,2,0,0,2,0,0,0,2,0,0,0,0,2,0,0,0,0,0,2,0,0,0,0,0,0,2,0,0,0,0,0,
%T A089799 0,0,2,0,0,0,0,0,0,0,0,2,0,0,0,0,0,0,0,0,0,2,0,0,0,0,0,0,0,0,0,0,2,0,
%U A089799 0,0,0,0,0,0,0,0,0,0,2,0,0,0,0,0,0,0,0,0,0,0,0,2,0,0,0,0,0,0,0,0,0,0
%N A089799 Expansion of Jacobi theta function theta_2(q^(1/2))/q^(1/8).
%H A089799 G. C. Greubel, <a href="/A089799/b089799.txt">Table of n, a(n) for n = 0..5000</a>
%H A089799 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/JacobiThetaFunctions.html">Jacobi Theta Functions</a>
%H A089799 I. J. Zucker, <a href="https://doi.org/10.1088/0305-4470/23/2/009">Further Relations Amongst Infinite Series and Products. II. The Evaluation of Three-Dimensional Lattice Sums</a>, J. Phys. A: Math. Gen. 23, 117-132, 1990.
%t A089799 a[n_] := SeriesCoefficient[ EllipticTheta[2, 0, q^(1/2)]/q^(1/8), {q, 0, n}]; Table[a[n], {n, 0, 101}] (* _Jean-François Alcover_, Nov 12 2012 *)
%K A089799 nonn
%O A089799 0,1
%A A089799 _Eric W. Weisstein_, Nov 12 2003