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A362891
Expansion of e.g.f. 1/(1 + LambertW(x^2 * log(1-x))).
1
1, 0, 0, 6, 12, 40, 1620, 11088, 80640, 2289600, 30471840, 374663520, 9819817920, 195106129920, 3507260492736, 95860364846400, 2466492401318400, 58909563259223040, 1775000008437557760, 54856736708999339520, 1629826915777548364800
OFFSET
0,4
LINKS
Eric Weisstein's World of Mathematics, Lambert W-Function.
FORMULA
a(n) = n! * Sum_{k=0..floor(n/3)} k^k * |Stirling1(n-2*k,k)|/(n-2*k)!.
PROG
(PARI) my(N=20, x='x+O('x^N)); Vec(serlaplace(1/(1+lambertw(x^2*log(1-x)))))
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, May 08 2023
STATUS
approved