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 A366980 #40 Nov 01 2023 17:16:40
%S A366980 1,1,4,24,171,1336,11060,95298,845649,7675398,70921457,664905445,
%T A366980 6309060313,60473691666,584684295383,5695312881404,55839455579659,
%U A366980 550621231581791,5457218248143692,54332533436452743,543148496962279730,5449742750024662824
%N A366980 G.f. satisfies A(x) = 1 + x*A(x)^5 * (1 - x*A(x)).
%F A366980 a(n) = Sum_{k=0..n} (-1)^(n-k) * binomial(n+4*k+1,k) * binomial(k,n-k)/(n+4*k+1).
%o A366980 (PARI) a(n) = sum(k=0, n, (-1)^(n-k)*binomial(n+4*k+1, k)*binomial(k, n-k)/(n+4*k+1));
%Y A366980 Cf. A000108, A200754.
%Y A366980 Cf. A365185, A367017.
%K A366980 nonn
%O A366980 0,3
%A A366980 _Seiichi Manyama_, Nov 01 2023