A218430 Numbers k for which sigma(k)/k - 2/9 is an integer.

54, 2744280, 6191640, 182494620, 653425920, 702989280, 27025270272, 72475361280, 76172903718912, 15224461545984768, 1688635722988634112, 5953066676035614584064, 1608903162935227680030720, 14600472124349965895417376, 2263986000385276007625523200

Offset: 1

Author

Zdenek Cervenka, Oct 28 2012

Keywords

• nonn

Comments

a(9) > 10^11. - Donovan Johnson, Nov 01 2012

a(9) > 10^12. - Giovanni Resta, Nov 04 2012

Note that there are no terms here with abundancy 11/9 (k=1) or 29/9 (k=3). - Michel Marcus, Jun 25 2013

Crossrefs

Cf. A218414, A160320, A218415, A218416, A160321, A218417, A218418.

Extensions

a(4)-a(8) from Donovan Johnson, Nov 01 2012

More terms from Michel Marcus, Jun 25 2013