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 A369128 #17 Jan 15 2024 08:53:09
%S A369128 1,5,35,285,2530,23752,231910,2331040,23960235,250692365,2661086895,
%T A369128 28587333725,310217791590,3395464391870,37442295427120,
%U A369128 415570885425280,4638842010800025,52044582325415025,586553425250933055,6637525235622842585,75387741117556006435
%N A369128 Expansion of (1/x) * Series_Reversion( x / ((1+x)^5+x^5) ).
%H A369128 Seiichi Manyama, <a href="/A369128/b369128.txt">Table of n, a(n) for n = 0..924</a>
%H A369128 <a href="/index/Res#revert">Index entries for reversions of series</a>
%F A369128 a(n) = (1/(n+1)) * Sum_{k=0..floor(n/5)} binomial(n+1,k) * binomial(5*n-5*k+5,n-5*k).
%o A369128 (PARI) my(N=30, x='x+O('x^N)); Vec(serreverse(x/((1+x)^5+x^5))/x)
%o A369128 (PARI) a(n) = sum(k=0, n\5, binomial(n+1, k)*binomial(5*n-5*k+5, n-5*k))/(n+1);
%Y A369128 Cf. A071356, A192132, A369126.
%Y A369128 Cf. A364522.
%K A369128 nonn
%O A369128 0,2
%A A369128 _Seiichi Manyama_, Jan 14 2024