Thanks for the info smh and TTn. I'll take a look at fixedn sieving.
Now that I've tried out some of the k's in my table, I have another question.
Some k's like 8331405 have 14 primes in the top5000 from n=198433k.
Others I have searched n=187300k and found 0 top5000 primes. It looks
like the # of primes found in 010k isn't always a good predictor of larger primes
(unless the range happens to hit the arbitrarily large gaps between primes...).
Any pointers here?
thanks,
Larry
