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A218417 Numbers n for which sigma(n)/n = k+7/9 with integer k. 5
135, 216, 819, 2678400, 6780874383360, 15298997575680, 358160471832960, 878948428037760, 69640897897267200, 27548836016065625124864000, 114509071123027415138304000, 204540330952262537736192000, 32445066814696289084018688000, 42000317261222229165905510400 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

a(5) > 10^11. - Donovan Johnson, Nov 01 2012

a(5) > 10^12. - Giovanni Resta, Nov 04 2012

LINKS

Table of n, a(n) for n=1..14.

FORMULA

sigma(n)/n = k+7/9 with integer k.

CROSSREFS

Cf. A218414, A218430, A160320, A218415, A218416, A160321, A218418.

Sequence in context: A296451 A096593 A050215 * A274434 A325569 A342189

Adjacent sequences:  A218414 A218415 A218416 * A218418 A218419 A218420

KEYWORD

nonn

AUTHOR

Zdenek Cervenka, Oct 28 2012

EXTENSIONS

More terms from Michel Marcus, Jun 26 2013

STATUS

approved

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Last modified September 26 06:16 EDT 2021. Contains 347664 sequences. (Running on oeis4.)