OFFSET
1,1
COMMENTS
Except for the first term, all terms are congruent to 1 (mod 6). - John Cerkan, Sep 07 2016
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..1000
MAPLE
A023215:=n->`if`(isprime(n) and isprime(4*n+7), n, NULL): seq(A023215(n), n=1..3*10^3); # Wesley Ivan Hurt, Sep 07 2016
MATHEMATICA
Select[Prime[Range[300]], PrimeQ[4#+7]&] (* Harvey P. Dale, Jan 21 2011 *)
PROG
(Magma) [n: n in PrimesUpTo(500) | IsPrime(4*n+7)]; // Vincenzo Librandi, Nov 19 2010
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
STATUS
approved