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A347416
a(n) = Sum_{k=1..n} floor((n/k)^n).
3
1, 5, 31, 276, 3238, 47463, 830415, 16845619, 388198577, 10009945747, 285452668383, 8918294580680, 302912273410475, 11112687415252836, 437907284782655738, 18447025981637731050, 827246579683710818081, 39346558272075085340201, 1978423430905859200399397
OFFSET
1,2
LINKS
FORMULA
a(n) ~ n^n. - Vaclav Kotesovec, Sep 14 2021
EXAMPLE
a(3) = [(3/1)^3] + [(3/2)^3] + [(3/3)^3] = 27 + 3 + 1 = 31.
MATHEMATICA
a[n_] := Sum[Floor[(n/k)^n], {k, 1, n}]; Array[a, 20] (* Amiram Eldar, Aug 31 2021 *)
PROG
(PARI) a(n) = sum(k=1, n, n^n\k^n);
CROSSREFS
KEYWORD
nonn
AUTHOR
Seiichi Manyama, Aug 31 2021
STATUS
approved