Quote:
Originally Posted by rogue
None that I know of. You can search any even base. I would expect even base 4 to have some primes.

Base 4 is covered by base 2 (since 4^n = 2^(2n)). Similarly, any perfect power will be covered by its base. So, 4,8,16,32,36,etc... need not be searched.
EDIT: I'll work on base12 to 50,000. I'll sieve base18 to 100,000 but not sure how far I'm willing to test. Will know further once I'm done with base12.