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A075071
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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.
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4
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1, 2, 6, 12, 120, 60, 5040, 840, 60480, 15120, 39916800, 2310, 6227020800, 8648640, 1816214400, 10810800, 355687428096000, 2042040, 121645100408832000, 116396280, 1689515283456000, 14079294028800, 25852016738884976640000
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OFFSET
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1,2
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COMMENTS
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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.
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LINKS
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EXAMPLE
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a(12) = 12! / (2!*3!*4!*6!) = 2310.
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MATHEMATICA
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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 *)
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CROSSREFS
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KEYWORD
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nice,nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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