A129614 - OEIS

%I #2 Mar 30 2012 17:37:44

%S 2,2,4,16,346,390410,390410,34712918410,40501164004

%N a(n) is the smallest natural number m such that 3^(3^k) + m is prime for k=0,1,...,n.

%C Next term is greater than 2*10^8.

%e For k=0,1,...,6 3^3^k + 390410 are prime and 390410 is the smallest number with this property so a(6)=390410.

%Y Cf. A129613, A129615.

%K hard,more,nonn

%O 0,1

%A _Farideh Firoozbakht_, May 13 2007, Jun 01 2007