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A069150
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Integers of the form k*k!/A062758(k) in the order they appear in A069149, where A062758(k) is the product of squares of divisors of k.
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0
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1, 2, 24, 720, 4480, 3628800, 1925, 479001600, 387459072, 20922789888000, 6402373705728000, 5516784599040000, 1124000727777607680000, 135277939046250, 24817936069329577574400, 553211880832106496000000
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OFFSET
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1,2
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LINKS
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MATHEMATICA
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Rest[Select[Table[k! k/(Times@@Divisors[k])^2, {k, 30}], IntegerQ]] (* Harvey P. Dale, Oct 17 2020 *)
Select[(# * #! / #^DivisorSigma[0, #]) & /@ Range[2, 30], IntegerQ] (* Amiram Eldar, Jul 16 2022 *)
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PROG
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(PARI) for(n=2, 30, if((n*(n!))%(n^numdiv(n))==0, print1((n*(n!))/(n^numdiv(n)), ", ")))
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CROSSREFS
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KEYWORD
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easy,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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