cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A218415 Numbers k for which sigma(k)/k - 4/9 is an integer.

Original entry on oeis.org

9, 1782, 2160, 5400, 13104, 52141320, 117641160, 173365920, 6829038720, 12415092480, 13356796320, 104381747712, 513480135168, 1377031864320, 6578372828160, 26896578508800, 294208373809152, 1447285170659328, 3151812152130048, 7734746166732288
Offset: 1

Views

Author

Zdenek Cervenka, Oct 28 2012

Keywords

Comments

a(12) > 10^11. - Donovan Johnson, Nov 01 2012
a(14) > 10^12. - Giovanni Resta, Nov 04 2012

Crossrefs

Cf. A218414, A218430, A160320, A218416, A160321, A218417, A218418.

Extensions

a(6)-a(11) from Donovan Johnson, Nov 01 2012
a(12)-a(13) from Giovanni Resta, Nov 04 2012
More terms from Michel Marcus, Jun 25 2013

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