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A141643 Numbers n such that sigma(n)/n = 5/2. 7
24, 91963648, 10200236032 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

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

No more terms below 10^12. - Jud McCranie, Aug 30 2013

LINKS

Table of n, a(n) for n=1..3.

Walter Nissen, Abundancy : Some Resources

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: A294326 A255322 A172803 * A275026 A013910 A007458

Adjacent sequences:  A141640 A141641 A141642 * A141644 A141645 A141646

KEYWORD

nonn,more,bref

AUTHOR

Yasutoshi Kohmoto, May 10 2008

EXTENSIONS

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

First three terms confirmed by Ray Chandler, Sep 18 2008

STATUS

approved

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Last modified November 18 02:54 EST 2017. Contains 294840 sequences.