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A049433
Numbers n such that n!-(n-1)!-1 is prime.
5
3, 4, 6, 8, 9, 12, 28, 78, 99, 184, 286, 291, 398, 411, 600, 718, 732, 889, 1963, 2240, 2242, 2533, 8800, 11403
OFFSET
1,1
COMMENTS
There is no further term up to 1400. - Farideh Firoozbakht, Jul 18 2003
a(25) > 12000. [From Donovan Johnson, Dec 18 2009]
EXAMPLE
6!-(6-1)!-1 = 599 is prime.
CROSSREFS
KEYWORD
nonn
AUTHOR
Paul Jobling (paul.jobling(AT)whitecross.com)
EXTENSIONS
More terms from Farideh Firoozbakht, Jul 18 2003
Corrected offset, edited definition and a(19)-a(24) from Donovan Johnson, Dec 18 2009
STATUS
approved