Quote:
Originally Posted by henryzz
how often are we expecting primes in this drive
i have found five primes and have tested 7200 numbers
i expected more primes

Assuming average k/base/n of 1100*2^2750001 for 3600 candidates and 1100*2^1250001 for 3600 candidates (to get a slightly more accurate value due to the extremely varying nrange) and sieve depth of 1800000000000 (1800G), you should expect 3.037 (2.088 from the lower range and 0.949 from the higher range) primes, so you're actually well above average.