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 A369156 #12 Jan 15 2024 09:03:02
%S A369156 1,4,22,140,968,7064,53544,417456,3326304,26967040,221733568,
%T A369156 1844667136,15498804480,131325820032,1120928667264,9628975973120,
%U A369156 83181462291968,722175844640768,6297942966129664,55143987250677760,484589284705202176,4272491458636754944
%N A369156 Expansion of (1/x) * Series_Reversion( x / ((1+x)^4-x^4) ).
%H A369156 <a href="/index/Res#revert">Index entries for reversions of series</a>
%F A369156 a(n) = (1/(n+1)) * Sum_{k=0..floor(n/4)} (-1)^k * binomial(n+1,k) * binomial(4*n-4*k+4,n-4*k).
%o A369156 (PARI) my(N=30, x='x+O('x^N)); Vec(serreverse(x/((1+x)^4-x^4))/x)
%o A369156 (PARI) a(n) = sum(k=0, n\4, (-1)^k*binomial(n+1, k)*binomial(4*n-4*k+4, n-4*k))/(n+1);
%Y A369156 Cf. A107264, A369157.
%Y A369156 Cf. A317133, A369126.
%K A369156 nonn
%O A369156 0,2
%A A369156 _Seiichi Manyama_, Jan 15 2024