OFFSET
1,1
COMMENTS
Primes of the form 10*A000215(n) + 9. - Arkadiusz Wesolowski, Mar 04 2011
a(n) is composite for n = 0 and all 8 <= n <= 26. - Arkadiusz Wesolowski, Oct 21 2013
LINKS
G. L. Honaker, Jr. and Chris Caldwell, Prime Curios! 9
MATHEMATICA
Select[Table[10*2^2^n + 19, {n, 0, 7}], PrimeQ] (* Arkadiusz Wesolowski, Mar 04 2011 *)
PROG
(Magma) [10*2^2^n+19 : n in [0..7] | IsPrime(10*2^2^n+19)]; // Arkadiusz Wesolowski, Mar 04 2011
(PARI) for(n=0, 7, if(isprime(x=(10*2^2^n+19)), print1(x, ", "))); \\ Arkadiusz Wesolowski, Mar 04 2011
CROSSREFS
KEYWORD
nonn,hard
AUTHOR
Arkadiusz Wesolowski, May 23 2009
STATUS
approved