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A369722
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Expansion of e.g.f. exp( (3/2) * (1-sqrt(1-4*x)) ).
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3
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1, 3, 15, 117, 1305, 19323, 359559, 8084205, 213425361, 6475518675, 222088463199, 8497641269637, 358899729493545, 16585866328129803, 832523413971932055, 45105537151437499197, 2623613865509122341921, 163070009495928522691875
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OFFSET
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0,2
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LINKS
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FORMULA
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a(0) = 1; a(n) = Sum_{k=0..n-1} 3^(n-k) * (n-1+k)! / (k! * (n-1-k)!).
a(n) = 2*(2*n-3)*a(n-1) + 9*a(n-2).
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PROG
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(PARI) my(N=20, x='x+O('x^N)); Vec(serlaplace(exp(3/2*(1-sqrt(1-4*x)))))
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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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