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 A370838 #10 Mar 03 2024 09:53:00
%S A370838 1,1,1,1,0,-4,-14,-34,-64,-80,16,496,1946,5266,10830,14886,-884,
%T A370838 -92564,-390404,-1113380,-2405649,-3529749,-360799,20509101,91770476,
%U A370838 271807476,608858576,941203576,243522996,-4977842140,-23564569004,-72054072364,-166314098964
%N A370838 Expansion of (1/x) * Series_Reversion( x/(x+1/(1+x^4)) ).
%H A370838 <a href="/index/Res#revert">Index entries for reversions of series</a>
%F A370838 a(n) = Sum_{k=0..floor(n/4)} (-1)^k * binomial(n,4*k) * binomial(5*k,k)/(4*k+1).
%o A370838 (PARI) my(N=40, x='x+O('x^N)); Vec(serreverse(x/(x+1/(1+x^4)))/x)
%o A370838 (PARI) a(n) = sum(k=0, n\4, (-1)^k*binomial(n, 4*k)*binomial(5*k, k)/(4*k+1));
%Y A370838 Cf. A370836, A370837.
%Y A370838 Cf. A227035, A370801.
%K A370838 sign
%O A370838 0,6
%A A370838 _Seiichi Manyama_, Mar 03 2024