A219221 Numbers n such that sigma(n)*tau(n) is a perfect number.

2, 13, 3554677, 7339129, 8125441, 910156807, 2080358881, 14914915687

Offset

1,1

Comments

a(9) > A002182(111). - Donovan Johnson, Aug 22 2013

Links

Table of n, a(n) for n=1..8.

Formula

Numbers n such that sigma(n)*tau(n) is a perfect number.

Crossrefs

Cf. A000005, A000203, A000396.

Sequence in context: A262299 A135970 A027738 * A249510 A324219 A349877

Adjacent sequences: A219218 A219219 A219220 * A219222 A219223 A219224

Keyword

nonn

Author

Zdenek Cervenka, Nov 15 2012

Extensions

a(6)-a(7) from Donovan Johnson, Nov 15 2012

a(8) from Donovan Johnson, Aug 22 2013

Status

approved