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 A366095 #10 Sep 29 2023 10:04:29
%S A366095 1,1,1,2,5,11,25,63,162,415,1085,2896,7795,21127,57785,159253,441351,
%T A366095 1229506,3442150,9678358,27315923,77364683,219815829,626375327,
%U A366095 1789627564,5125729137,14714078483,42327358520,121998755959,352272227623,1018915014521
%N A366095 Expansion of (1/x) * Series_Reversion( x*(1+x-x^3)/(1+x)^2 ).
%F A366095 a(n) = (1/(n+1)) * Sum_{k=0..floor(n/3)} binomial(n+k,k) * binomial(n-k+1,n-3*k).
%o A366095 (PARI) a(n) = sum(k=0, n\3, binomial(n+k, k)*binomial(n-k+1, n-3*k))/(n+1);
%Y A366095 Cf. A366071, A366096, A366097.
%K A366095 nonn
%O A366095 0,4
%A A366095 _Seiichi Manyama_, Sep 29 2023