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 A366595 #12 Oct 14 2023 13:19:45
%S A366595 1,0,0,0,1,3,3,1,4,24,60,80,82,222,796,1848,2912,4452,11088,31592,
%T A366595 70467,125437,231105,551775,1399069,3068219,5942937,12017739,27966515,
%U A366595 66675777,145719483,298344501,632955999,1449806573,3346606719,7335193353,15557399668
%N A366595 G.f. A(x) satisfies A(x) = 1 + x^4*(1+x)^3*A(x)^4.
%F A366595 a(n) = Sum_{k=0..floor(n/4)} binomial(3*k,n-4*k) * binomial(4*k,k)/(3*k+1).
%o A366595 (PARI) a(n) = sum(k=0, n\4, binomial(3*k, n-4*k)*binomial(4*k, k)/(3*k+1));
%Y A366595 Cf. A366272, A366593, A366594.
%Y A366595 Cf. A366589, A366592.
%Y A366595 Cf. A366558.
%K A366595 nonn
%O A366595 0,6
%A A366595 _Seiichi Manyama_, Oct 14 2023