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A038157
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a(n) = n! * Sum_{k=1..n-2} 1/k!.
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3
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0, 0, 0, 6, 36, 200, 1230, 8652, 69272, 623520, 6235290, 68588300, 823059732, 10699776672, 149796873590, 2246953104060, 35951249665200, 611171244308672, 11001082397556402, 209020565553571980, 4180411311071439980, 87788637532500240000
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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) = floor(n!*exp(1)) - n - 1 - n! for n>1. - Mark van Hoeij, Oct 30 2011
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MATHEMATICA
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Table[n!Sum[1/k!, {k, n-2}], {n, 0, 30}] (* Harvey P. Dale, Dec 26 2021 *)
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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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