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A362304
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a(n) = n! * Sum_{k=0..floor(n/3)} (-n/3)^k * binomial(n-2*k,k)/(n-2*k)!.
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4
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1, 1, 1, -5, -31, -99, 1201, 13231, 70785, -1362311, -21562399, -161746749, 4263108961, 87979472725, 849097038609, -28416142768649, -723086288422399, -8532476619366159, 346207723221680065, 10474480743776327179, 146105160034616914401
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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^3/3).
E.g.f.: exp( ( LambertW(x^3) )^(1/3) ) / (1 + LambertW(x^3)).
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PROG
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(PARI) my(N=30, x='x+O('x^N)); Vec(serlaplace(exp(lambertw(x^3)^(1/3))/(1+lambertw(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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