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A218430 Numbers k for which sigma(k)/k - 2/9 is an integer. 5
54, 2744280, 6191640, 182494620, 653425920, 702989280, 27025270272, 72475361280, 76172903718912, 15224461545984768, 1688635722988634112, 5953066676035614584064, 1608903162935227680030720, 14600472124349965895417376, 2263986000385276007625523200 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
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
LINKS
CROSSREFS
Sequence in context: A347061 A151635 A363458 * A159732 A174946 A182119
KEYWORD
nonn
AUTHOR
Zdenek Cervenka, Oct 28 2012
EXTENSIONS
a(4)-a(8) from Donovan Johnson, Nov 01 2012
More terms from Michel Marcus, Jun 25 2013
STATUS
approved

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Last modified April 20 00:00 EDT 2024. Contains 371798 sequences. (Running on oeis4.)