A152178 Smallest prime factor of G-n, where G is any sufficiently large power tower of 3, e.g., Graham's number.

3, 2, 5, 2, 107, 2, 3, 2, 101, 2, 29, 2, 3, 2, 13, 2, 3626257, 2, 3, 2, 7, 2, 5, 2, 3, 2, 1511, 2, 173, 2, 3, 2, 5, 2, 7, 2, 3, 2, 197, 2, 13, 2, 3, 2, 17491, 2, 18540593, 2, 3, 2, 53, 2, 5, 2, 3, 2, 19, 2, 17, 2, 3, 2, 5, 2, 11, 2, 3, 2, 29, 2, 97, 2, 3, 2, 251, 2, 7, 2, 3, 2, 349, 2, 5, 2, 3, 2