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A055204
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Squarefree part of n!: n! divided by its largest square divisor.
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19
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1, 2, 6, 6, 30, 5, 35, 70, 70, 7, 77, 231, 3003, 858, 1430, 1430, 24310, 12155, 230945, 46189, 969969, 176358, 4056234, 676039, 676039, 104006, 312018, 44574, 1292646, 1077205, 33393355, 66786710, 2203961430, 64822395, 90751353, 90751353
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OFFSET
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1,2
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COMMENTS
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Smallest number such that n!*a(n) is a square.
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LINKS
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FORMULA
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EXAMPLE
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10! = 518400*7 = 7*(720)^2, so a(10) = 7.
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MATHEMATICA
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Table[#/Last@ Select[Divisors@ #, IntegerQ@ Sqrt@ # &] &[n!], {n, 26}] (* Michael De Vlieger, May 02 2016 *)
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PROG
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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