A371023 E.g.f. satisfies log(A(x)) = x*A(x)^2 * (exp(x*A(x)^2) - 1).
1, 0, 2, 3, 112, 665, 23016, 292957, 10710960, 223877313, 9010822600, 266949248621, 12012620436312, 461111201730049, 23286625765980864, 1093225826724243045, 61822510319788946656, 3415325919719802626177, 215162865022831595415576
Offset: 0
Keywords
Programs
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PARI
a(n) = n!*sum(k=0, n\2, (2*n+1)^(k-1)*stirling(n-k, k, 2)/(n-k)!);
Formula
a(n) = n! * Sum_{k=0..floor(n/2)} (2*n+1)^(k-1) * Stirling2(n-k,k)/(n-k)!.