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 A366101 #10 Sep 29 2023 10:04:55
%S A366101 1,0,0,0,0,1,-1,1,-1,1,5,-12,20,-29,39,1,-109,305,-611,1051,-1145,139,
%T A366101 3055,-9924,22424,-37574,43476,-14035,-97831,368715,-852385,1470767,
%U A366101 -1823523,885634,3444224,-14239745,34089723,-61051093,80200515,-48234695,-123155951
%N A366101 Expansion of (1/x) * Series_Reversion( x*(1+x-x^5)/(1+x) ).
%F A366101 a(n) = (1/(n+1)) * Sum_{k=0..floor(n/5)} (-1)^(n-k) * binomial(n+k,k) * binomial(n-4*k-1,n-5*k).
%o A366101 (PARI) a(n) = sum(k=0, n\5, (-1)^(n-k)*binomial(n+k, k)*binomial(n-4*k-1, n-5*k))/(n+1);
%Y A366101 Cf. A366071, A366102.
%K A366101 sign
%O A366101 0,11
%A A366101 _Seiichi Manyama_, Sep 29 2023