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A076891 a(n) = [n/1][n/2][n/3] ...[n/n] / n^(tau(n)/2). 2
1, 1, 1, 1, 2, 1, 6, 2, 8, 6, 60, 2, 288, 48, 84, 60, 3840, 48, 15552, 144, 4800, 10080, 221760, 96, 331776, 138240, 224640, 25920, 20321280, 4032, 108864000, 345600, 17694720, 36495360, 51701760, 40320, 11287019520, 627056640, 992839680 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,5
LINKS
FORMULA
a(n) = A010786(n)/n^(A000005(n)/2) = A010786(n)/A007955(n).
MATHEMATICA
a[n_] := Product[Floor[n/k], {k, 1, n}] / n^(DivisorSigma[0, n]/2); Array[a, 40] (* Amiram Eldar, Apr 08 2024 *)
PROG
(PARI) a(n) = prod(k = 1, n, n\k) / n^(numdiv(n)/2); \\ Amiram Eldar, Apr 08 2024
CROSSREFS
Cf. A000005 (tau), A007955, A010786.
Sequence in context: A195441 A338025 A239537 * A071883 A368241 A099304
KEYWORD
nonn
AUTHOR
Benoit Cloitre, Nov 26 2002
STATUS
approved

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Last modified May 11 05:30 EDT 2024. Contains 372388 sequences. (Running on oeis4.)