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A363356
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E.g.f. satisfies A(x) = exp(x * A(x) * (1 + x * A(x)^3)).
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1
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1, 1, 5, 52, 821, 17536, 473497, 15476224, 594230345, 26221431808, 1307680266221, 72739285725184, 4465197522732157, 299855584017743872, 21867349264346912705, 1721013285639521959936, 145394112130209844644113, 13123788855563296766427136
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OFFSET
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0,3
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LINKS
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FORMULA
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a(n) = n! * Sum_{k=0..n} (3*n-2*k+1)^(k-1) * binomial(k,n-k)/k!.
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PROG
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(PARI) a(n) = n!*sum(k=0, n, (3*n-2*k+1)^(k-1)*binomial(k, n-k)/k!);
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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