A377325 E.g.f. satisfies A(x) = 1 - log(1 - x*A(x))/A(x).
1, 1, 1, 5, 28, 244, 2566, 33438, 508544, 8926944, 176989488, 3917823216, 95719041408, 2559130965312, 74312569125744, 2329169772108528, 78371469374088960, 2817744760964392704, 107807187260426164992, 4373419962377871956736, 187507942522161269068800
Offset: 0
Keywords
Programs
-
PARI
a(n) = sum(k=0, (n+1)\2, (n-k)!/(n-2*k+1)!*abs(stirling(n, k, 1)));
Formula
a(n) = Sum_{k=0..floor((n+1)/2)} (n-k)!/(n-2*k+1)! * |Stirling1(n,k)|.