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A347416
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a(n) = Sum_{k=1..n} floor((n/k)^n).
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3
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1, 5, 31, 276, 3238, 47463, 830415, 16845619, 388198577, 10009945747, 285452668383, 8918294580680, 302912273410475, 11112687415252836, 437907284782655738, 18447025981637731050, 827246579683710818081, 39346558272075085340201, 1978423430905859200399397
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OFFSET
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1,2
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LINKS
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FORMULA
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EXAMPLE
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a(3) = [(3/1)^3] + [(3/2)^3] + [(3/3)^3] = 27 + 3 + 1 = 31.
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MATHEMATICA
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a[n_] := Sum[Floor[(n/k)^n], {k, 1, n}]; Array[a, 20] (* Amiram Eldar, Aug 31 2021 *)
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PROG
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(PARI) a(n) = sum(k=1, n, n^n\k^n);
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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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