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 A366042 #8 Sep 27 2023 10:05:59
%S A366042 1,1,2,5,14,43,139,465,1595,5577,19805,71240,259037,950590,3516110,
%T A366042 13095440,49068051,184839543,699607625,2659276675,10147039881,
%U A366042 38853068780,149240187330,574913637375,2220609902199,8598120578442,33366877654697,129758691426484
%N A366042 Expansion of (1/x) * Series_Reversion( x*(1-x)*(1-x^5) ).
%F A366042 a(n) = (1/(n+1)) * Sum_{k=0..floor(n/5)} binomial(n+k,n) * binomial(2*n-5*k,n).
%o A366042 (PARI) a(n) = sum(k=0, n\5, binomial(n+k, n)*binomial(2*n-5*k, n))/(n+1);
%Y A366042 Cf. A006013, A063020, A063030, A366041.
%Y A366042 Cf. A366024.
%K A366042 nonn
%O A366042 0,3
%A A366042 _Seiichi Manyama_, Sep 26 2023