%I #12 Sep 29 2023 09:27:47
%S 1,2,7,30,142,715,3756,20349,112864,637659,3656775,21229923,124531256,
%T 736920158,4393859967,26371222935,159193382812,965923527255,
%U 5887659026592,36034716884127,221362690616841,1364404640452602,8435444693847402
%N Expansion of (1/x) * Series_Reversion( x*(1-x)^3/(1-x-x^4) ).
%H Seiichi Manyama, <a href="/A366089/b366089.txt">Table of n, a(n) for n = 0..1000</a>
%F a(n) = (1/(n+1)) * Sum_{k=0..floor(n/4)} (-1)^k * binomial(n+1,k) * binomial(3*n-3*k+1,n-4*k).
%o (PARI) a(n) = sum(k=0, n\4, (-1)^k*binomial(n+1, k)*binomial(3*n-3*k+1, n-4*k))/(n+1);
%Y Cf. A366086, A366087, A366088, A366090.
%Y Cf. A366055.
%K nonn
%O 0,2
%A _Seiichi Manyama_, Sep 28 2023
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