OFFSET
1,1
COMMENTS
Primes p such that 9*p+2, 81*p+20, 729*p+182 and 6561*p+1640 are also primes. - Vincenzo Librandi, Aug 04 2010
LINKS
Harvey P. Dale, Table of n, a(n) for n = 1..1000
MATHEMATICA
Select[Prime[Range[11000]], AllTrue[Rest[NestList[9#+2&, #, 4]], PrimeQ]&] (* The program uses the AllTrue function from Mathematica version 10 *) (* Harvey P. Dale, Feb 12 2015 *)
PROG
(Magma) [n: n in [1..5000000] | IsPrime(n) and IsPrime(9*n+2) and IsPrime(81*n+20) and IsPrime(729*n+182) and IsPrime(6561*n+1640)] // Vincenzo Librandi, Aug 04 2010
CROSSREFS
KEYWORD
nonn
AUTHOR
STATUS
approved