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A048753
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Composite numbers k whose product of aliquot divisors divided by number of aliquot divisors is an integer.
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2
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4, 6, 15, 16, 20, 21, 27, 33, 36, 39, 42, 45, 48, 50, 51, 56, 57, 69, 70, 75, 87, 93, 100, 105, 111, 120, 123, 129, 132, 141, 154, 159, 162, 175, 177, 182, 183, 189, 196, 198, 201, 210, 213, 219, 220, 231, 237, 238, 245, 249, 256, 266, 267, 270, 273, 275, 291
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OFFSET
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1,1
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LINKS
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EXAMPLE
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For k=6, the product of aliquot divisors is 3*2*1=6; the number of aliquot divisors is 3; 6/3 = 2 (an integer), so 6 is a term.
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MATHEMATICA
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padQ[n_]:=Module[{ad=Most[Divisors[n]]}, !PrimeQ[n]&&Divisible[Times@@ad, Length[ad]]]; Select[Range[2, 300], padQ] (* Harvey P. Dale, May 07 2012 *)
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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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STATUS
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approved
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