

A088332


Primes of the form n! + 1.


18




OFFSET

1,1


COMMENTS

Of course 2 = 0! + 1 = 1! + 1 has two such representations.
Prime numbers that are the sum of two factorial numbers.  JuriStepan Gerasimov, Nov 08 2010


LINKS

T. D. Noe, Table of n, a(n) for n=1..11
R. Mestrovic, Euclid's theorem on the infinitude of primes: a historical survey of its proofs (300 BC2012) and another new proof, arXiv preprint arXiv:1202.3670, 2012  From N. J. A. Sloane, Jun 13 2012


EXAMPLE

3! + 1 = 7 is prime.


MATHEMATICA

lst={}; Do[p=n!+1; If[PrimeQ[p], AppendTo[lst, p]], {n, 0, 3*5!}]; lst (* Vladimir Joseph Stephan Orlovsky, Jan 27 2009 *)


PROG

(PARI) factp1prime(n)=for(x=1, n, xf=x!+1; if(isprime(xf), print1(xf", ")))


CROSSREFS

Cf. A002981 (values of n).
Sequence in context: A320432 A196303 A048979 * A131959 A202688 A021046
Adjacent sequences: A088329 A088330 A088331 * A088333 A088334 A088335


KEYWORD

nonn


AUTHOR

Cino Hilliard, Nov 06 2003


EXTENSIONS

The next term is too large to include.


STATUS

approved



