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 A368936 #10 Jan 10 2024 07:59:16
%S A368936 1,2,7,30,142,715,3756,20349,112865,637681,3657075,21233199,124562708,
%T A368936 737197980,4396176336,26389742175,159336837840,967007923321,
%U A368936 5895699043010,36093405644877,221785663880176,1367420967329725,8456765007380190,52447676008911675
%N A368936 Expansion of (1/x) * Series_Reversion( x * (1-x) * (1-x+x^4) ).
%F A368936 a(n) = (1/(n+1)) * Sum_{k=0..floor(n/4)} (-1)^k * binomial(n+k,k) * binomial(3*n-3*k+1,n-4*k).
%o A368936 (PARI) a(n) = sum(k=0, n\4, (-1)^k*binomial(n+k, k)*binomial(3*n-3*k+1, n-4*k))/(n+1);
%o A368936 (PARI) my(x='x+O('x^30)); Vec(serreverse(x*(1-x)*(1-x+x^4))/x) \\ _Michel Marcus_, Jan 10 2024
%Y A368936 Cf. A129442, A368935, A368937.
%Y A368936 Cf. A368932.
%K A368936 nonn
%O A368936 0,2
%A A368936 _Seiichi Manyama_, Jan 10 2024