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 A369161 #10 Jan 15 2024 09:04:03
%S A369161 1,3,15,91,613,4410,33190,258129,2058281,16737259,138268611,
%T A369161 1157197639,9790774861,83606543660,719638883748,6237175439640,
%U A369161 54386540912490,476782443732437,4199713449255749,37151346765537606,329914740292813170,2939975733035070000
%N A369161 Expansion of (1/x) * Series_Reversion( x * ((1-x)^3-x^4) ).
%H A369161 <a href="/index/Res#revert">Index entries for reversions of series</a>
%F A369161 a(n) = (1/(n+1)) * Sum_{k=0..floor(n/4)} binomial(n+k,k) * binomial(4*n-k+2,n-4*k).
%o A369161 (PARI) my(N=30, x='x+O('x^N)); Vec(serreverse(x*((1-x)^3-x^4))/x)
%o A369161 (PARI) a(n) = sum(k=0, n\4, binomial(n+k, k)*binomial(4*n-k+2, n-4*k))/(n+1);
%Y A369161 Cf. A063021, A369102, A369160.
%K A369161 nonn
%O A369161 0,2
%A A369161 _Seiichi Manyama_, Jan 15 2024