A357090 E.g.f. satisfies A(x) = (1 - x * A(x))^(log(1 - x * A(x)) * A(x)).
1, 0, 2, 6, 106, 1060, 21728, 396648, 10174764, 267855264, 8517836832, 289596897480, 11137252365600, 461124747706896, 20922578332613904, 1018268757357253920, 53372000211252229392, 2981808910524462942720, 177468245487057424475136
Offset: 0
Keywords
Programs
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PARI
a(n) = sum(k=0, n\2, (2*k)!*(n+k+1)^(k-1)*abs(stirling(n, 2*k, 1))/k!);
Formula
E.g.f. satisfies log(A(x)) = log(1 - x * A(x))^2 * A(x).
a(n) = Sum_{k=0..floor(n/2)} (2*k)! * (n+k+1)^(k-1) * |Stirling1(n,2*k)|/k!.