A092791 Numbers n such that (n-1)! + n is prime.

1, 2, 3, 5, 7, 11, 53, 6823, 30839

Offset

1,2

Comments

All terms beyond the first must be prime. [Charles R Greathouse IV, Apr 19 2013]

a(10) > 37000. - Giovanni Resta, May 04 2013

Links

Table of n, a(n) for n=1..9.

Mathematica

Select[Range[80], PrimeQ[(# - 1)! + #] &] (* Jayanta Basu, Apr 19 2013 *)

Prog

(PARI) pm1factpp(n) = { forprime(p=1, n, c=0; y=(p-1)!+p; if(isprime(y), print1(p", ")) ) }

Crossrefs

Sequence in context: A378775 A058253 A004089 * A070892 A075800 A067909

Adjacent sequences: A092788 A092789 A092790 * A092792 A092793 A092794

Keyword

nonn

Author

Cino Hilliard, Apr 15 2004

Extensions

a(8)-a(9) from Giovanni Resta, May 04 2013

Status

approved