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A159271 Numbers with abundancy index sigma(n)/n = 11/2. 11
17116004505600, 75462255348480000, 6219051710415667200, 14031414189615513600, 352444116692828160000, 835095457414213632000, 59485231752222033838080, 64031599488357236736000 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
G. P. Michon and M. Marcus, Hemiperfect numbers of abundancy 11/2 (table with factorizations). [From Gerard P. Michon, Jul 01 2009]
PROG
(PARI) is(n)=sigma(n, -1)==11/2 \\ Charles R Greathouse IV, Mar 09 2014
CROSSREFS
Sequence in context: A238357 A349028 A160935 * A288277 A297449 A321137
KEYWORD
nonn
AUTHOR
M. F. Hasler, Apr 21 2009
STATUS
approved

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Last modified April 30 23:38 EDT 2024. Contains 372141 sequences. (Running on oeis4.)