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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

Michel Marcus, Table of n, a(n) for n = 1..117

G. P. Michon and M. Marcus, Hemiperfect numbers of abundancy 11/2 (table with factorizations). [From Gerard P. Michon, Jul 01 2009]

Walter Nissen, Abundancy : Some Resources

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

Adjacent sequences:  A159268 A159269 A159270 * A159272 A159273 A159274

KEYWORD

nonn

AUTHOR

M. F. Hasler, Apr 21 2009

STATUS

approved

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Last modified November 26 08:23 EST 2022. Contains 358354 sequences. (Running on oeis4.)