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 A366054 #8 Sep 27 2023 10:06:14
%S A366054 1,1,2,5,15,49,168,594,2149,7919,29627,112254,429884,1661308,6470678,
%T A366054 25375070,100106145,397018815,1582005849,6330533220,25428891084,
%U A366054 102497788194,414445390730,1680617637425,6833083703094,27849689394894,113762630541908
%N A366054 Expansion of (1/x) * Series_Reversion( x*(1-x)^2/(1-x+x^4) ).
%F A366054 a(n) = (1/(n+1)) * Sum_{k=0..floor(n/4)} binomial(n+1,k) * binomial(2*n-3*k,n-4*k).
%o A366054 (PARI) a(n) = sum(k=0, n\4, binomial(n+1, k)*binomial(2*n-3*k, n-4*k))/(n+1);
%Y A366054 Cf. A215341, A366055, A366056.
%K A366054 nonn
%O A366054 0,3
%A A366054 _Seiichi Manyama_, Sep 27 2023