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 A320131 #11 Oct 07 2018 03:33:25 %S A320131 1,4,6,8,12,8,8,16,6,14,32,20,40,48,16,32,44,28,54,72,40,64,72,16,40, %T A320131 52,56,92,96,56,32,80,38,48,104,64,102,144,52,32,112,44,128,168,68, %U A320131 136,128,96,104,132,62,144,176,104,172,96,112,112,192,116,96,240,96,176 %N A320131 Number of integer solutions to a^2 + b^2 + 2*c^2 + 9*d^2 = n. %C A320131 a(n) > 0 for n >= 0. %H A320131 Seiichi Manyama, <a href="/A320131/b320131.txt">Table of n, a(n) for n = 0..10000</a> %F A320131 G.f.: theta_3(q)^2 * theta_3(q^2) * theta_3(q^9). %Y A320131 Cf. A097057, A320124, A320125, A320126, A320127, A320128, A320130, A320132, A320133, A320134, A320135, A320136. %K A320131 nonn %O A320131 0,2 %A A320131 _Seiichi Manyama_, Oct 06 2018