OFFSET
1,1
COMMENTS
For numbers k for which (5+k!)/5 is prime see A139058.
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10
FORMULA
MATHEMATICA
a = {}; Do[If[PrimeQ[(n! + 5)/5], AppendTo[a, (n! + 5)/5]], {n, 1, 50}]; a
Select[(5+Range[50]!)/5, PrimeQ] (* Harvey P. Dale, Dec 04 2020 *)
PROG
(Magma) [ a: n in [1..50] | IsPrime(a) and b mod 5 eq 0 where a is b div 5 where b is Factorial(n)+5 ];
(PARI) for(k=5, 1e3, if(ispseudoprime(t=(5+k!)/5), print1(t", "))) \\ Charles R Greathouse IV, Jul 15 2011
CROSSREFS
KEYWORD
nonn
AUTHOR
Artur Jasinski, Apr 07 2008
STATUS
approved