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A141643 Numbers n such that sigma(n)/n = 5/2. 5
24, 91963648, 10200236032 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

LINKS

Walter Nissen, Abundancy : Some Resources

Walter Nissen, Home Page (listed in lieu of email address)

G. P. Michon, Multiperfect and hemiperfect numbers

Walter Nissen, Abundancy : Some Resources

Walter Nissen, Primitive Friendly Pairs with friends < 2^34 with denom < 20000

CROSSREFS

Cf. A055153, A141645, A159271, A160678.

Sequence in context: A159191 A013820 A172803 * A013910 A007458 A072244

Adjacent sequences:  A141640 A141641 A141642 * A141644 A141645 A141646

KEYWORD

nonn,more,bref

AUTHOR

Yasutoshi Kohmoto (zbi74583(AT)boat.zero.ad.jp), May 10 2008

EXTENSIONS

Definition rewritten by M. F. Hasler, May 10 2008

First three terms confirmed by Ray Chandler (rayjchandler(AT)sbcglobal.net), Sep 18 2008.

There are no other terms though 2^34. - Walter Nissen Apr 17 2009

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Last modified February 17 12:23 EST 2012. Contains 206011 sequences.