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A131385 Product ceiling(n/1)*ceiling(n/2)*ceiling(n/3)*...*ceiling(n/n) (the 'ceiling factorial'). 5
1, 2, 6, 16, 60, 144, 672, 1536, 6480, 19200, 76032, 165888, 1048320, 2257920, 8294400, 28311552, 126904320, 268738560, 1470873600, 3096576000, 16094453760, 51385466880, 175814737920, 366917713920, 2717245440000 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

FORMULA

a(n)=product{1<=k<=n} ceiling(n/k).

MATHEMATICA

Table[Product[Ceiling[n/k], {k, n}], {n, 25}] (* From Harvey P. Dale, Sep 18 2011 *)

CROSSREFS

Cf. A010786, A131387.

Sequence in context: A068787 A073959 A006820 * A027742 A033301 A197102

Adjacent sequences:  A131382 A131383 A131384 * A131386 A131387 A131388

KEYWORD

nonn

AUTHOR

Hieronymus Fischer (Hieronymus.Fischer(AT)gmx.de), Jul 08 2007

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Last modified February 15 17:46 EST 2012. Contains 205835 sequences.