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A048886 Numbers n such that sigma(n) = n-th composite number. 0
6, 8, 10, 14, 27, 39, 51, 57, 745, 755, 7091, 268243, 439681, 3271489, 33559819, 74138989, 80194627, 179405777, 1131818923, 1170569879, 1324475807, 1324478657, 51086967247, 72229691441, 72229691533, 72229691993, 72229693511 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
PROG
(PARI) isok(n) = (sigma(n) == A002808(n)) \\ (see script there). Michel Marcus, Jul 14 2013
CROSSREFS
Sequence in context: A243537 A073582 A363837 * A349477 A161545 A350295
KEYWORD
nonn
AUTHOR
EXTENSIONS
a(15)-a(22) from Donovan Johnson, Apr 03 2008
a(23)-a(27) from Donovan Johnson, Oct 24 2010
STATUS
approved

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Last modified February 29 14:32 EST 2024. Contains 370425 sequences. (Running on oeis4.)