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 A063201 #10 Aug 22 2019 12:18:12
%S A063201 0,1,3,2,4,5,5,6,8,7,9,10,10,11,13,12,14,15,15,16,18,17,19,20,20,21,
%T A063201 23,22,24,25,25,26,28,27,29,30,30,31,33,32,34,35,35,36,38,37,39,40,40,
%U A063201 41
%N A063201 Dimension of the space of weight 2n cuspidal newforms for Gamma_0( 18 ).
%H A063201 R. J. Mathar, <a href="/A063201/b063201.txt">Table of n, a(n) for n = 1..1000</a>
%H A063201 G. Martin, <a href="http://dx.doi.org/10.1016/j.jnt.2004.10.009">Dimensions of the spaces of cusp forms and newforms on Gamma_0(N) and Gamma_1(N)</a>, J. Numb. Theory 112 (2005) 298-331, Theorem 1
%H A063201 William A. Stein, <a href="http://wstein.org/Tables/dimskg0new.gp">Dimensions of the spaces S_k^{new}(Gamma_0(N))</a>
%H A063201 William A. Stein, <a href="http://wstein.org/Tables/">The modular forms database</a>
%H A063201 <a href="/index/Rec#order_05">Index entries for linear recurrences with constant coefficients</a>, signature (0,1,1,0,-1).
%F A063201 G.f.: x^2*(1+3*x+x^2) / ( (1+x)*(1+x+x^2)*(x-1)^2 ). - _R. J. Mathar_, Jul 15 2015
%K A063201 nonn
%O A063201 1,3
%A A063201 _N. J. A. Sloane_, Jul 10 2001