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A064121 Nonprime numbers n such that the sum of aliquot divisors of n (A001065) and product of aliquot divisors of n (A048741) are both perfect squares. 2
1, 12, 75, 76, 124, 147, 153, 176, 243, 332, 363, 477, 507, 524, 575, 688, 867, 892, 963, 1075, 1083, 1421, 1532, 1573, 1587, 1611, 1916, 2032, 2075, 2224, 2299, 2401, 2421, 2523, 2572, 2883, 2891, 3100, 3479, 3776, 3888, 4107, 4336, 4527, 4961, 4975 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

MATHEMATICA

Select[ Range[5000], IntegerQ[ Sqrt[ Apply[ Plus, Delete[ Divisors[ # ], -1]]]] && IntegerQ[ Sqrt[ Apply[ Times, Delete[Divisors[ # ], -1]]]] && ! PrimeQ[ # ] & ]

CROSSREFS

Variant of A064116. - R. J. Mathar, Oct 02 2008

Cf. A064710.

Sequence in context: A156196 A041270 A055912 * A064116 A003368 A246767

Adjacent sequences:  A064118 A064119 A064120 * A064122 A064123 A064124

KEYWORD

easy,nonn

AUTHOR

Robert G. Wilson v, Oct 14 2001

STATUS

approved

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Last modified February 26 08:15 EST 2020. Contains 332277 sequences. (Running on oeis4.)