A367489 Expansion of e.g.f. -x * log(3 - 2*exp(x)).
0, 0, 4, 18, 120, 1110, 13140, 189042, 3197040, 62093358, 1361253900, 33236925546, 894243758760, 26281928034726, 837663638344260, 28775491618091490, 1059805146165293280, 41657455054069680414, 1740535210734651716220, 77029901631623181859674
Offset: 0
Programs
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PARI
a(n) = n*sum(k=1, n-1, 2^k*(k-1)!*stirling(n-1, k, 2));
Formula
a(n) = n * Sum_{k=1..n-1} 2^k * (k-1)! * Stirling2(n-1,k).