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 A369124 #11 Jan 14 2024 08:56:05
%S A369124 1,4,26,204,1770,16352,157696,1569096,15988652,165998624,1749696208,
%T A369124 18673883696,201394693864,2191421381632,24028822589440,
%U A369124 265238416143584,2944999336948944,32869042668479424,368551132961138784,4149643380825661824,46897527236429235520
%N A369124 Expansion of (1/x) * Series_Reversion( x * ((1-x)^4+x^4) ).
%H A369124 <a href="/index/Res#revert">Index entries for reversions of series</a>
%F A369124 a(n) = (1/(n+1)) * Sum_{k=0..floor(n/4)} (-1)^k * binomial(n+k,k) * binomial(5*n+3,n-4*k).
%o A369124 (PARI) my(N=30, x='x+O('x^N)); Vec(serreverse(x*((1-x)^4+x^4))/x)
%o A369124 (PARI) a(n) = sum(k=0, n\4, (-1)^k*binomial(n+k, k)*binomial(5*n+3, n-4*k))/(n+1);
%Y A369124 Cf. A097188, A369123, A369125.
%Y A369124 Cf. A369102.
%K A369124 nonn
%O A369124 0,2
%A A369124 _Seiichi Manyama_, Jan 13 2024