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A362305
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a(n) = n! * Sum_{k=0..floor(n/3)} (-n)^k * binomial(n-2*k,k)/(n-2*k)!.
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4
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1, 1, 1, -17, -95, -299, 12241, 122011, 642433, -41645015, -597247199, -4407324569, 390913189921, 7315513279933, 69439658097265, -7816418805235949, -180448412456686079, -2093964182367814319, 285679499679525805633, 7844019340520912230495
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OFFSET
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0,4
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LINKS
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FORMULA
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a(n) = n! * [x^n] exp(x - n*x^3).
E.g.f.: exp( ( LambertW(3*x^3)/3 )^(1/3) ) / (1 + LambertW(3*x^3)).
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PROG
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(PARI) my(N=20, x='x+O('x^N)); Vec(serlaplace(exp((lambertw(3*x^3)/3)^(1/3))/(1+lambertw(3*x^3))))
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CROSSREFS
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KEYWORD
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sign
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AUTHOR
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STATUS
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approved
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