OFFSET
1,1
COMMENTS
Except for the first term, all terms are congruent to 5 (mod 6). - John Cerkan, Sep 07 2016
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..2000
MAPLE
A023218:=n->`if`(isprime(n) and isprime(5*n+4), n, NULL): seq(A023218(n), n=1..2*10^3); # Wesley Ivan Hurt, Sep 07 2016
MATHEMATICA
lst={}; Do[If[PrimeQ[n]&&PrimeQ[5*n+4], AppendTo[lst, n]], {n, 13^3}]; lst (* Vladimir Joseph Stephan Orlovsky, Sep 08 2008 *)
Select[Prime[Range[300]], PrimeQ[5#+4]&] (* Harvey P. Dale, Dec 31 2013 *)
PROG
(Magma) [n: n in [0..1000] | IsPrime(n) and IsPrime(5*n+4)]; // Vincenzo Librandi, Nov 20 2010
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved