
COMMENTS

The sequence with the unknown terms indicated by ?: 2, 3, 2, 3, 444, ?, 2, ?, 2, 3, ?, 5, 2, 3, 2, 3, ?, 19, 2, 3, 4, 19, 6, ?, 2, 3, 2, 15, 30, 7, 6, 3, 2, 3, 6, ?, 2, 5, 2, 3, ...
The unknown terms a(6), a(8), a(11), a(17), a(24), a(36) are > 6000.
It is conjectured that such x always exists.  Dean Hickerson
We can show that for all n=(6k1)^3, k > 0, there is no such x, which disproves the conjecture. See the main entry A087037 for more details.  Farideh Firoozbakht and M. F. Hasler, Nov 27 2009
