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A226238
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a(n) = (n^n - n)/(n - 1).
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5
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2, 12, 84, 780, 9330, 137256, 2396744, 48427560, 1111111110, 28531167060, 810554586204, 25239592216020, 854769755812154, 31278135027204240, 1229782938247303440, 51702516367896047760, 2314494592664502210318, 109912203092239643840220
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OFFSET
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2,1
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COMMENTS
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a(n) expressed in base n is written with (n-1) ones followed by a zero. - Michel Marcus, Aug 25 2013
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LINKS
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FORMULA
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a(n) = Sum_{k=1..n-1} n^k.
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MATHEMATICA
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PROG
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(PARI) a(n)=(n^n-n)/(n-1)
(Python)
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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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