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A368576
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a(n) = n! * Sum_{k=0..n} binomial(k+4,5) / k!.
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3
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0, 1, 8, 45, 236, 1306, 8088, 57078, 457416, 4118031, 41182312, 453008435, 5436105588, 70669378832, 989371312216, 14840569694868, 237449115133392, 4036634957288013, 72659429231210568, 1380529155393034441, 27610583107860731324, 579822245265075410934
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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(0) = 0; a(n) = n*a(n-1) + binomial(n+4,5).
E.g.f.: x * (1+2*x+x^2+x^3/6+x^4/120) * exp(x) / (1-x).
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PROG
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(PARI) my(N=30, x='x+O('x^N)); concat(0, Vec(serlaplace(x*sum(k=0, 4, binomial(4, k)*x^k/(k+1)!)*exp(x)/(1-x))))
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CROSSREFS
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KEYWORD
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nonn,easy
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AUTHOR
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STATUS
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approved
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