A129615 - OEIS

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A129615

a(n) is the smallest natural number m such that 4^4^k + m is prime for k=0,1,...,n.

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

%S 1,1,15,385,137593,106908087

%N a(n) is the smallest natural number m such that 4^4^k + m is prime for k=0,1,...,n.

%C Next term is greater than 3*10^8.

%e For k=0,1,...,5 4^4^k + 106908087 are prime and 106908087 is the smallest number with this property so a(5)=106908087.

%Y Cf. A129613, A129614.

%K hard,more,nonn

%O 0,3

%A _Farideh Firoozbakht_, May 13 2007