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A048741
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Product of aliquot divisors of composite n (1 and primes omitted).
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3
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2, 6, 8, 3, 10, 144, 14, 15, 64, 324, 400, 21, 22, 13824, 5, 26, 27, 784, 27000, 1024, 33, 34, 35, 279936, 38, 39, 64000, 74088, 1936, 2025, 46, 5308416, 2500, 51, 2704, 157464, 55, 175616, 57, 58, 777600000, 62, 3969, 32768, 65, 287496, 4624, 69
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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REFERENCES
| Albert H. Beiler, Recreations in the Theory of Numbers, 2nd ed., pages 10, 23. New York: Dover, 1966. ISBN 0-486-21096-0.
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EXAMPLE
| The third composite number is 8, for which the product of aliquot divisors is 4*2*1 = 8, so a(3)=8.
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MATHEMATICA
| Composite[n_] := FixedPoint[n + PrimePi[ # ] + 1 &, n + PrimePi[n] + 1]; Table[ Times @@ Select[ Divisors[ Composite[n]], # < Composite[n] & ], {n, 1, 60} ]
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CROSSREFS
| This is A007956 omitting the 1's.
Cf. A007422, A007956, A048740.
Sequence in context: A019786 A067067 A119279 * A115317 A117932 A073411
Adjacent sequences: A048738 A048739 A048740 * A048742 A048743 A048744
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KEYWORD
| easy,nonn
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AUTHOR
| Enoch Haga (Enokh(AT)comcast.net)
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