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A060917 Expansion of e.g.f.: exp((-1)^k/k*LambertW(-x)^k)/(k-1)!, k=3. 4
1, 12, 150, 2180, 36855, 715008, 15697948, 385300800, 10463945085, 311697869120, 10108450408914, 354630018043392, 13384651003544275, 540860323696035840, 23300648262667635960, 1066165291831917811712 (list; graph; refs; listen; history; text; internal format)
OFFSET

3,2

COMMENTS

a(n) = A243098(n,3)/2. - Alois P. Heinz, Aug 19 2014

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 3..200

FORMULA

a(n) = (n-1)!/(k-1)!*Sum_{i=0..floor((n-k)/k)} 1/(i!*k^i)*n^(n-(i+1)*k)/(n-(i+1)*k)!, k=3.

a(n) ~ 1/2*exp(1/3)*n^(n-1). - Vaclav Kotesovec, Nov 27 2012

MATHEMATICA

nn = 20; CoefficientList[Series[E^(-1/3*LambertW[-x]^3)/2, {x, 0, nn}], x]* Range[0, nn]! (* Vaclav Kotesovec, Nov 27 2012 *)

PROG

(PARI) x='x+O('x^30); Vec(serlaplace(exp(-lambertw(-x)^3/3)/2 - 1/2)) \\ G. C. Greubel, Feb 19 2018

CROSSREFS

Cf. A057817, A060918, A243098.

Sequence in context: A264233 A068768 A053507 * A113358 A293153 A015611

Adjacent sequences:  A060914 A060915 A060916 * A060918 A060919 A060920

KEYWORD

easy,nonn

AUTHOR

Vladeta Jovovic, Apr 10 2001

STATUS

approved

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Last modified November 23 17:10 EST 2020. Contains 338595 sequences. (Running on oeis4.)