A055490 Factorial primes: primes of the form n! - 1.

5, 23, 719, 5039, 479001599, 87178291199, 265252859812191058636308479999999, 263130836933693530167218012159999999, 8683317618811886495518194401279999999

Offset: 1

Author

Labos Elemer, Jun 28 2000

Keywords

• nonn

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

References

• James J. Tattersall, Elementary Number Theory in Nine Chapters, Cambridge University Press, 1999, page 118.

Links

• T. D. Noe, Table of n, a(n) for n=1..12

Crossrefs

Cf. A000142, A000203, A002982.

Programs

Mathematica

Select[Range[40]!-1,PrimeQ] (* Harvey P. Dale, Aug 16 2012 *)

Formula

p = n!-1 for some n given in A002982.

Extensions

Edited by Jon E. Schoenfield, Jan 09 2015