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A218414 Numbers k for which sigma(k)/k - 1/9 is an integer. 5
540, 3276, 58032, 950976, 1862190, 17660160, 3925389312, 1005014679552, 16080326885376, 17908023591648, 43947421401888, 92069057203200, 207726054681600, 411471933675264, 12363050673792000, 160893693946908502272, 269783631952374398976, 467406267507560908800 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
a(8) > 10^11. - Donovan Johnson, Nov 01 2012
a(8) > 10^12. - Giovanni Resta, Nov 04 2012
Note that there are no terms with abundancy 10/9 (k=1) or 19/9 (k=2). Michel Marcus, Jun 25 2013
LINKS
CROSSREFS
Sequence in context: A185463 A069474 A253824 * A328133 A146123 A159207
KEYWORD
nonn
AUTHOR
Zdenek Cervenka, Oct 28 2012
EXTENSIONS
a(6)-a(7) from Donovan Johnson, Nov 01 2012
More terms from Michel Marcus, Jun 25 2013
STATUS
approved

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Last modified April 23 08:33 EDT 2024. Contains 371905 sequences. (Running on oeis4.)