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A317421
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a(n) = Sum_{k=1..n} binomial(n-1,k-1)*prime(k)*n!/k!.
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0
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2, 7, 35, 223, 1711, 15283, 155333, 1766819, 22205615, 305275979, 4553222111, 73179347509, 1260129395189, 23135381385341, 450963438488267, 9298480714769813, 202154606388513675, 4620729025472999443, 110759284511324893795, 2777748141259276697671, 72735279236489471934853
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OFFSET
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1,1
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COMMENTS
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Lah transform of the primes.
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LINKS
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FORMULA
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E.g.f.: Sum_{k>=1} prime(k)*(x/(1 - x))^k/k!.
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MATHEMATICA
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Table[Sum[Binomial[n - 1, k - 1] Prime[k] n!/k!, {k, n}], {n, 21}]
nmax = 21; Rest[CoefficientList[Series[Sum[Prime[k] (x/(1 - x))^k/k!, {k, nmax}], {x, 0, nmax}], x] Range[0, nmax]!]
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PROG
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(PARI) for(n=1, 30, print1(sum(k=1, n, binomial(n-1, k-1)*prime(k)*n!/k!), ", ")) \\ G. C. Greubel, Jul 28 2018
(Magma) [(&+[Binomial(n-1, k-1)*NthPrime(k)*Factorial(n)/Factorial(k): k in [1..n]]): n in [1..30]]; // G. C. Greubel, Jul 28 2018
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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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