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A162947
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Numbers n such the product of all divisors of n equals n^3.
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0
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1, 12, 18, 20, 28, 32, 44, 45, 50, 52, 63, 68, 75, 76, 92, 98, 99, 116, 117, 124, 147, 148, 153, 164, 171, 172, 175, 188, 207, 212, 236, 242, 243, 244, 245, 261, 268, 275, 279, 284, 292, 316, 325, 332, 333, 338, 356, 363, 369, 387, 388, 404, 412, 423, 425, 428
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| Contains the terms of A054753 (products p*q^2 of a prime p and a different prime q), 1, and p^5, where p is prime.
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FORMULA
| {n: A007955(n) = A000578(n)}. R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jul 19 2009
{1} UNION A030515. - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jul 19 2009
n such that n^2 = product of proper divisors of n. - Juri-Stepan Gerasimov (2stepan(AT)rambler.ru), May 03 2011.
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EXAMPLE
| 18 is in the sequence because the product of its divisors = 1*2*3*6*9*18 = 18^3.
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CROSSREFS
| Cf. A111398, A030628. - R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jul 19 2009
Sequence in context: A153501 A181595 A030515 * A070011 A084679 A072588
Adjacent sequences: A162944 A162945 A162946 * A162948 A162949 A162950
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KEYWORD
| nonn
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AUTHOR
| Claudio L Meller (claudiomeller(AT)gmail.com), Jul 18 2009
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EXTENSIONS
| Edited by R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Jul 19 2009
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