OFFSET
1,1
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..1000
MATHEMATICA
Select[Range[2000], PrimeQ[7 # + 1]&& PrimeQ[7 # - 1]&] (* Vincenzo Librandi, Apr 05 2013 *)
PROG
(Magma) [n: n in [1..2000] | IsPrime(7*n+1) and IsPrime(7*n-1)]
CROSSREFS
KEYWORD
nonn,easy
AUTHOR
Vincenzo Librandi, Mar 08 2010
STATUS
approved