OFFSET
1,1
COMMENTS
Primes p such that 3*p+8, 9*p+32, 27*p+104 and 81*p+320 are also primes. - Vincenzo Librandi, Aug 04 2010
LINKS
John Cerkan, Table of n, a(n) for n = 1..10000
FORMULA
a(n) == 1 or 31 (mod 70). - John Cerkan, Oct 04 2016
MATHEMATICA
okQ[n_]:=And@@PrimeQ/@Rest[NestList[3#+8&, n, 4]]; Select[Prime[Range[60000]], okQ] (* Harvey P. Dale, Aug 16 2010 *)
PROG
(Magma) [n: n in [1..1000000] | IsPrime(n) and IsPrime(3*n+8) and IsPrime(9*n+32) and IsPrime(27*n+104) and IsPrime(81*n+320)] // Vincenzo Librandi, Aug 04 2010
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved