A356787 E.g.f. satisfies A(x) = 1/(1 - x * A(x))^(x * A(x)^3).
1, 0, 2, 3, 116, 630, 24054, 273000, 11105072, 207213552, 9175467960, 245785969440, 11954556125544, 421832039016960, 22609694372667024, 991695134898861120, 58565049582761702400, 3065736317041568378880, 199024242549235933723200
Offset: 0
Keywords
Programs
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PARI
a(n) = n!*sum(k=0, n\2, (n+2*k+1)^(k-1)*abs(stirling(n-k, k, 1))/(n-k)!);
Formula
a(n) = n! * Sum_{k=0..floor(n/2)} (n+2*k+1)^(k-1) * |Stirling1(n-k,k)|/(n-k)!.