A362273 Expansion of e.g.f. 1/(1 - x * exp(-x * exp(-x))).
1, 1, 0, 3, 8, -15, 264, -35, -1968, 87633, -499600, 2375901, 48964200, -830424023, 9884072184, -11730111315, -1407884197216, 36601422429345, -416600839315872, 191233500832189, 136472124267672120, -3513232740127917639, 46653752740647748520
Offset: 0
Keywords
Links
- Winston de Greef, Table of n, a(n) for n = 0..455
Programs
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PARI
my(N=30, x='x+O('x^N)); Vec(serlaplace(1/(1-x*exp(-x*exp(-x)))))
Formula
a(n) = n! * Sum_{i=0..n} (-1)^(n-i) * Sum_{j=0..n-i} i^j * j^(n-i-j) / (j! * (n-i-j)!).