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A218417
Numbers k for which sigma(k)/k - 7/9 is an integer.
5
135, 216, 819, 2678400, 6780874383360, 15298997575680, 358160471832960, 878948428037760, 69640897897267200, 27548836016065625124864000, 114509071123027415138304000, 204540330952262537736192000, 32445066814696289084018688000, 42000317261222229165905510400
OFFSET
1,1
COMMENTS
a(5) > 10^11. - Donovan Johnson, Nov 01 2012
a(5) > 10^12. - Giovanni Resta, Nov 04 2012
KEYWORD
nonn
AUTHOR
Zdenek Cervenka, Oct 28 2012
EXTENSIONS
More terms from Michel Marcus, Jun 26 2013
STATUS
approved