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A071248
a(n) = Product_{k=1..n} lcm(n,k).
4
1, 4, 54, 768, 75000, 466560, 592950960, 5284823040, 1735643790720, 45360000000000, 1035338990313196800, 102980960177356800, 145077660657859734604800, 154452450072526199193600
OFFSET
1,2
COMMENTS
Log(a(n))/n/Log(n) is bounded since n^n < a(n) < n^(2n). It seems that lim n -> infinity Log(a(n))/n/Log(n) exists and = 1.7.... - Benoit Cloitre, Aug 13 2002
FORMULA
a(n) = n!*Product_{ d divides n } d^phi(d). - Vladeta Jovovic, Sep 10 2004
a(n) = n!*n^n/A067911(n)=A000142(n)*A000312(n)/A067911(n). - R. J. Mathar, Apr 03 2007
MAPLE
A071248 := proc(n) mul( lcm(k, n), k=1..n) ; end: for n from 1 to 10 do printf("%d ", A071248(n)) ; od ; # R. J. Mathar, Apr 03 2007
MATHEMATICA
Table[Product[LCM[k, n], {k, n}], {n, 20}] (* Harvey P. Dale, Jun 12 2019 *)
PROG
(PARI) a(n)=prod(k=1, n, lcm(n, k))
CROSSREFS
Product of terms in n-th row of A051173.
Sequence in context: A089205 A294041 A055774 * A221611 A303048 A304556
KEYWORD
nonn
AUTHOR
Amarnath Murthy, May 21 2002
EXTENSIONS
More terms from Benoit Cloitre, Aug 13 2002
STATUS
approved