A363478 E.g.f. satisfies A(x) = exp(x * (1 + x) * A(x)^3).
1, 1, 9, 142, 3481, 115476, 4849639, 246746662, 14756605329, 1014635520424, 78869009859751, 6839463570354306, 654661145565724345, 68559809182824171148, 7797979656027302949159, 957275139494698134599806, 126152927575064012671549729
Offset: 0
Keywords
Links
- Eric Weisstein's World of Mathematics, Lambert W-Function.
Programs
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PARI
my(N=20, x='x+O('x^N)); Vec(serlaplace(exp(-lambertw(-3*x*(1+x))/3)))
Formula
E.g.f.: exp( -LambertW(-3*x * (1+x))/3 ).
a(n) = n! * Sum_{k=0..n} (3*k+1)^(k-1) * binomial(k,n-k)/k!.