|
| |
|
|
A055490
|
|
Factorial primes: primes of the form n!-1.
|
|
9
| |
|
|
5, 23, 719, 5039, 479001599, 87178291199, 265252859812191058636308479999999, 263130836933693530167218012159999999, 8683317618811886495518194401279999999
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,1
|
|
|
COMMENTS
| For further information see A002982, which is the main entry.
Also primes of the form [(n!-1) mod (n-1)! ], with n>=1. - Paolo P. Lava & Giorgio Balzarotti (paoloplava(AT)gmail.com), Mar 14 2007. [For (n!-1) mod (n-1)! only produces numbers of
Also primes of the form 1*1! + 2*2! + ... + n*n!. Example: 1*1! + 2*2! + 3*3! + 4*4! + 5*5! + 6*6! + 7*7! + 8*8! + 9*9! + 10*10! + 11*11! + 12*12! + 13*13! = 87178291199 is prime. - Jonathan Vos Post (jvospost3(AT)gmail.com), Jul 21 2006
Prime numbers that are the difference between two factorial numbers. [From Juri-Stepan Gerasimov (2stepan(AT)rambler.ru), Nov 08 2010]
|
|
|
LINKS
| T. D. Noe, Table of n, a(n) for n=1..12
|
|
|
FORMULA
| p = n!-1 for some n given in A002982
a(n)=A000040(k)=A000142(m)-A000142(s). [From Juri-Stepan Gerasimov (2stepan(AT)rambler.ru), Nov 08 2010]
|
|
|
MATHEMATICA
| lst={}; Do[p=n!-1; If[PrimeQ[p], AppendTo[lst, p]], {n, 0, 5*5!}]; lst [From Vladimir Orlovsky (4vladimir(AT)gmail.com), Jan 27 2009]
|
|
|
CROSSREFS
| Cf. A002982, A000203, A000142.
Sequence in context: A080990 A172036 A003487 * A002811 A177134 A199361
Adjacent sequences: A055487 A055488 A055489 * A055491 A055492 A055493
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Labos E. (labos(AT)ana.sote.hu), Jun 28 2000
|
| |
|
|
