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 A063033 #21 Mar 24 2023 16:16:32
%S A063033 0,1,1,2,4,8,14,16,-21,-242,-1166,-4472,-15132,-46508,-130016,-323000,
%T A063033 -660535,-786714,1789952,18546464,93845290,380532240,1355983860,
%U A063033 4363436280,12688926510,32530717752,67666586472,76255301640,-240266135872
%N A063033 Reversion of y - y^2 + y^4.
%H A063033 Michael De Vlieger, <a href="/A063033/b063033.txt">Table of n, a(n) for n = 0..800</a>
%H A063033 Elżbieta Liszewska, Wojciech Młotkowski, <a href="https://arxiv.org/abs/1907.10725">Some relatives of the Catalan sequence</a>, arXiv:1907.10725 [math.CO], 2019.
%H A063033 <a href="/index/Res#revert">Index entries for reversions of series</a>
%F A063033 a(n) = Sum_{j=0..(n-1)/2} (-1)^j*binomial(n-2*j-1, j)*binomial(2*n-2*j-2, n-1)/n, a(0)=0. - _Vladimir Kruchinin_, Oct 11 2011
%F A063033 D-finite with recurrence 391*n*(n-1)*(n-2)*a(n) -8*(n-1)*(n-2)*(203*n -132)*a(n-1) -4*(n-2)*(224*n^2 -2816*n +5697)*a(n-2) +8*(928*n^3 -7920*n^2 +22682*n-21915)*a(n-3) +192*(4*n-15) *(2*n-7)*(4*n-17)*a(n-4)=0, n-4>=1 - _R. J. Mathar_, Mar 24 2023
%t A063033 CoefficientList[InverseSeries[Series[y - y^2 + y^4, {y, 0, 30}], x], x]
%o A063033 (Maxima)
%o A063033 a(n):=sum((-1)^j*binomial(n-2*j-1,j)*binomial(2*n-2*j-2,n-1),j,0,(n-1)/2)/n; /* _Vladimir Kruchinin_, Oct 11 2011 */
%o A063033 (PARI) concat(0, Vec(serreverse(y - y^2 + y^4 + O(y^10)))) \\ _Michel Marcus_, Jun 28 2018
%K A063033 sign,easy
%O A063033 0,4
%A A063033 _Olivier Gérard_, Jul 05 2001