OFFSET
1,1
LINKS
Vincenzo Librandi, Table of n, a(n) for n = 1..4000
EXAMPLE
6*7=42, 42-5=37, 42-1=41, 37 and 41 primes.
MATHEMATICA
okQ[n_]:=Module[{x=6n}, PrimeQ[x-1]&&PrimeQ[x-5]]; Select[Prime[Range[ 500]], okQ] (* Harvey P. Dale, May 25 2011 *)
Select[Prime[Range[400]], PrimeQ[6 # - 5] && PrimeQ[6 # - 1]&] (* Vincenzo Librandi, May 23 2017 *)
PROG
(Magma) [p: p in PrimesUpTo(3000) |IsPrime(6*p-5) and IsPrime(6*p-1)]; // Vincenzo Librandi, May 23 2017
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Pierre CAMI, Dec 05 2003
EXTENSIONS
More terms from Ray Chandler, Dec 06 2003
STATUS
approved