OFFSET
1,1
COMMENTS
Generalized Fermat primes of the form b^(2^i) + k.
EXAMPLE
a(5) = 58 because k = 58 is the minimal k such that N = 3^(2^i) + k is prime for i = 0, 1, 2 ,3 ,4; N = 61, 67, 139, 6619, 43046779. But 3^(2^5) + 58 is divisible by 37 and three other primes.
CROSSREFS
KEYWORD
nonn,more
AUTHOR
Robin Garcia, Jun 02 2013
EXTENSIONS
a(11) from Giovanni Resta, Jun 17 2013
STATUS
approved