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A075071 n! divided by product of factorials of all proper divisors of n, as n runs through the values for which the result is an integer. 4
1, 2, 6, 12, 120, 60, 5040, 840, 60480, 15120, 39916800, 2310, 6227020800, 8648640, 1816214400, 10810800, 355687428096000, 2042040, 121645100408832000, 116396280, 1689515283456000, 14079294028800, 25852016738884976640000 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
n! divided by the product of factorials of all proper divisors of n is not always an integer; e.g., when n = 24 the quotient is 7436429/48. See A075422.
LINKS
EXAMPLE
a(12) = 12! / (2!*3!*4!*6!) = 2310.
MATHEMATICA
Select[Table[ n!/ Apply[ Times, Drop[ Divisors[n], -1]! ], {n, 1, 23}], IntegerQ]
Select[Table[n!/Times@@(Most[Divisors[n]]!), {n, 30}], IntegerQ] (* Harvey P. Dale, Aug 01 2020 *)
CROSSREFS
Cf. A075422.
Sequence in context: A038787 A144098 A259140 * A250269 A193987 A089423
KEYWORD
nice,nonn
AUTHOR
Amarnath Murthy, Sep 09 2002
EXTENSIONS
Edited by Robert G. Wilson v, Sep 14 2002
First Mathematica program modified by Harvey P. Dale, Aug 01 2020
STATUS
approved

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Last modified April 24 22:17 EDT 2024. Contains 371964 sequences. (Running on oeis4.)