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A088332 Primes of the form n!+1. 13
2, 3, 7, 39916801, 10888869450418352160768000001, 13763753091226345046315979581580902400000001, 33452526613163807108170062053440751665152000000001 (list; graph; refs; listen; history; text; internal format)
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. [From Juri-Stepan 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 BC--2012) 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 [From 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: A088252 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

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Last modified November 25 21:44 EST 2014. Contains 250010 sequences.