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 A367658 #8 Nov 26 2023 08:37:38
%S A367658 1,2,5,13,34,89,234,615,1616,4246,11156,29314,77026,202394,531811,
%T A367658 1397387,3671781,9647988,25351094,66612640,175031647,459913889,
%U A367658 1208471657,3175385173,8343655339,21923823599,57607130438,151368736483,397737124030,1045095727865
%N A367658 G.f. A(x) satisfies A(x) = 1 / (1 - x - x * (1 + x + x^2 + x^3 + x^4) * A(x^5)).
%F A367658 a(0) = 1; a(n) = a(n-1) + Sum_{k=0..n-1} a(floor(k/5)) * a(n-1-k).
%o A367658 (PARI) a_vector(n) = my(v=vector(n+1)); v[1]=1; for(i=1, n, v[i+1]=v[i]+sum(j=0, i-1, v[j\5+1]*v[i-j])); v;
%Y A367658 Cf. A367655, A367656, A367657.
%Y A367658 Cf. A367654, A367661.
%K A367658 nonn
%O A367658 0,2
%A A367658 _Seiichi Manyama_, Nov 26 2023