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 A366084 #13 Sep 29 2023 09:08:55
%S A366084 1,2,7,29,132,637,3199,16536,87366,469556,2558610,14100033,78437805,
%T A366084 439838596,2483300228,14103794518,80517436710,461768157262,
%U A366084 2658979794811,15366500638407,89093023210674,518064484263918,3020484579372765,17653011431832906
%N A366084 Expansion of (1/x) * Series_Reversion( x*(1-x)^3/(1-x-x^3) ).
%H A366084 Seiichi Manyama, <a href="/A366084/b366084.txt">Table of n, a(n) for n = 0..1000</a>
%F A366084 a(n) = (1/(n+1)) * Sum_{k=0..floor(n/3)} (-1)^k * binomial(n+1,k) * binomial(3*n-2*k+1,n-3*k).
%o A366084 (PARI) a(n) = sum(k=0, n\3, (-1)^k*binomial(n+1, k)*binomial(3*n-2*k+1, n-3*k))/(n+1);
%Y A366084 Cf. A049133, A243157, A366085.
%Y A366084 Cf. A366052.
%K A366084 sign
%O A366084 0,2
%A A366084 _Seiichi Manyama_, Sep 28 2023