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.

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

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: A041270 A055912 A346446 * A064116 A003368 A246767

Adjacent sequences: A064118 A064119 A064120 * A064122 A064123 A064124

Keyword

easy,nonn

Author

Robert G. Wilson v, Oct 14 2001

Status

approved