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A058807 a(n) = Product_{k=1..n} s(n,k), where s(n,k) is unsigned Stirling number of the first kind. (s(n,k) = number of permutations of n elements which contain exactly k cycles.) 5
1, 1, 6, 396, 420000, 9432450000, 5571367220160000, 103458225408290423193600, 70288262635020872178876253470720, 1993179010286886206697449779415040000000000, 2650683735711909138223088071500675703191552000000000000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Vaclav Kotesovec, Table of n, a(n) for n = 1..36

FORMULA

log(a(n)) ~ n^2 * (log(n) + Pi^2/6 - 3/2) / 2. - Vaclav Kotesovec, Feb 27 2021

EXAMPLE

a(4) = s(4,1)*s(4,2)*s(4,3)*s(4,4) = 6*11*6*1 = 396.

MAPLE

a:=n->mul(abs(Stirling1(n, k)), k=1..n): seq(a(n), n=1..10); # Zerinvary Lajos, Jun 28 2007

MATHEMATICA

Abs[Table[Product[StirlingS1[n, k], {k, n}], {n, 10}]] (* Harvey P. Dale, Oct 18 2014 *)

CROSSREFS

Cf. A058808, A132393, A294373.

Sequence in context: A290324 A306887 A289894 * A000474 A291593 A029591

Adjacent sequences:  A058804 A058805 A058806 * A058808 A058809 A058810

KEYWORD

easy,nonn

AUTHOR

Leroy Quet, Jan 02 2001

EXTENSIONS

a(11) from Harvey P. Dale, Oct 18 2014

STATUS

approved

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Last modified June 17 05:17 EDT 2021. Contains 345080 sequences. (Running on oeis4.)