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 A371367 #11 Mar 20 2024 09:39:40
%S A371367 1,7,97,1675,32353,669103,14491441,324479203,7450571905,174479758615,
%T A371367 4151241723265,100060420474555,2438221991122657,59964761207220415,
%U A371367 1486507438771416529,37105090783548992659,931807879987468872193,23525616974931980536615
%N A371367 Expansion of (1/x) * Series_Reversion( x * (1-6*x)^2 / (1-5*x) ).
%H A371367 <a href="/index/Res#revert">Index entries for reversions of series</a>
%F A371367 a(n) = (1/(n+1)) * Sum_{k=0..n} 5^(n-k) * binomial(2*n+k+1,k) * binomial(2*n,n-k).
%o A371367 (PARI) my(N=20, x='x+O('x^N)); Vec(serreverse(x*(1-6*x)^2/(1-5*x))/x)
%o A371367 (PARI) a(n) = sum(k=0, n, 5^(n-k)*binomial(2*n+k+1, k)*binomial(2*n, n-k))/(n+1);
%Y A371367 Cf. A078018.
%K A371367 nonn
%O A371367 0,2
%A A371367 _Seiichi Manyama_, Mar 19 2024