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A055490
Factorial primes: primes of the form n! - 1.
15
5, 23, 719, 5039, 479001599, 87178291199, 265252859812191058636308479999999, 263130836933693530167218012159999999, 8683317618811886495518194401279999999
OFFSET
1,1
COMMENTS
For further information see A002982, which is the main entry.
Also primes of the form 1*1! + 2*2! + ... + n*n!. - Jonathan Vos Post, Jul 21 2006
Prime numbers that are the difference of two factorial numbers. - Juri-Stepan Gerasimov, Nov 08 2010
LINKS
FORMULA
p = n!-1 for some n given in A002982.
MATHEMATICA
Select[Range[40]!-1, PrimeQ] (* Harvey P. Dale, Aug 16 2012 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Labos Elemer, Jun 28 2000
EXTENSIONS
Edited by Jon E. Schoenfield, Jan 09 2015
STATUS
approved