OFFSET
1,1
COMMENTS
For numbers k for which (4+k!)/4 is prime see A139061.
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..15
FORMULA
MATHEMATICA
a = {}; Do[If[PrimeQ[(n! + 4)/4], AppendTo[a, (n! + 4)/4]], {n, 1, 50}]; a
Select[(4+Range[100]!)/4, PrimeQ] (* Harvey P. Dale, Oct 05 2016 *)
PROG
(PARI) for(k=4, 1e3, if(ispseudoprime(t=k!/4+1), print1(t", "))) \\ Charles R Greathouse IV, Jul 15 2011
CROSSREFS
KEYWORD
nonn
AUTHOR
Artur Jasinski, Apr 07 2008
STATUS
approved