A362736 E.g.f. satisfies A(x) = exp(x^2 + x / A(x)).
1, 1, 1, 4, -3, 96, -755, 10368, -147623, 2492416, -47137959, 996741120, -23260103339, 594198429696, -16492683271259, 494278721929216, -15908038836914895, 547238863907586048, -20038031401448021327, 778147549666716155904, -31943565308583934360019
Offset: 0
Keywords
Links
- Eric Weisstein's World of Mathematics, Lambert W-Function.
Programs
-
PARI
my(N=30, x='x+O('x^N)); Vec(serlaplace(exp(x^2+lambertw(x*exp(-x^2)))))
Formula
E.g.f.: x / LambertW(x*exp(-x^2)) = exp( x^2 + LambertW(x*exp(-x^2)) ).
a(n) = n! * Sum_{k=0..floor(n/2)} (-n+2*k+1)^(n-k-1) / (k! * (n-2*k)!).