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 A378466 #10 Nov 27 2024 08:06:20
%S A378466 1,2,10,63,444,3351,26490,216523,1815080,15519271,134817972,
%T A378466 1186570526,10557959696,94817735251,858333997230,7823946906726,
%U A378466 71751021314438,661541649024816,6128551736153622,57018343512420580,532529776531703666,4991007108135966433
%N A378466 Expansion of (1/x) * Series_Reversion( x * (1 - x - x/(1 - x)^2) ).
%H A378466 <a href="/index/Res#revert">Index entries for reversions of series</a>
%F A378466 G.f.: exp( Sum_{k>=1} A378461(k) * x^k/k ).
%F A378466 a(n) = (1/(n+1)) * [x^n] 1/(1 - x - x/(1 - x)^2)^(n+1).
%F A378466 a(n) = (1/(n+1)) * Sum_{k=0..n} binomial(n+k,k) * binomial(2*n+2*k,n-k).
%o A378466 (PARI) my(N=30, x='x+O('x^N)); Vec(serreverse(x*(1-x-x/(1-x)^2))/x)
%o A378466 (PARI) a(n) = sum(k=0, n, binomial(n+k, k)*binomial(2*n+2*k, n-k))/(n+1);
%Y A378466 Cf. A151374, A378465.
%Y A378466 Cf. A378461.
%K A378466 nonn
%O A378466 0,2
%A A378466 _Seiichi Manyama_, Nov 27 2024