%I #9 Aug 22 2023 07:57:17
%S 1,1,-4,6,16,-119,240,630,-5656,13044,31568,-323102,816172,1772553,
%T -20373748,55339784,105991968,-1366239119,3950894080,6570520544,
%U -95534073488,292319792622,414994066768,-6884779019086,22198354364212,26341578132594,-507524582140912
%N G.f. satisfies A(x) = 1 + x / (1 + x*A(x))^4.
%F If g.f. satisfies A(x) = 1 + x/(1 + x*A(x))^s, then a(n) = Sum_{k=0..n} (-1)^(n-k) * binomial(n-k+1,k) * binomial(n+(s-1)*k-1,n-k)/(n-k+1).
%o (PARI) a(n, s=4) = sum(k=0, n, (-1)^(n-k)*binomial(n-k+1, k)*binomial(n+(s-1)*k-1, n-k)/(n-k+1));
%Y Cf. A007440, A365109, A365110, A365112.
%Y Cf. A365087.
%K sign
%O 0,3
%A _Seiichi Manyama_, Aug 22 2023
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