View Single Post
Old 2005-03-11, 00:49   #2
rogue's Avatar
Apr 2003
Between here and the

19×313 Posts

Originally Posted by jasong
Hey, guys, I would like to sieve until the sieving rate is JUUUUUUUUST under the average prp rate. Assuming that the minimum and maximum exponent are known and they increase at a steady rate(is this a good assumption?) how do I figure out the average length of time for a test?

Btw, I've sieved these already, but have no idea if I've reached the goal stated above.
I assume you are using PRP, LLR or PFGW. It should be fairly easy. This is what I do (assuming fixed k as opposed to fixed n). Here is an example from which you can extrapolate:

low k = 50000
high k = 200000

Calculate midk where midk = 200000 - (200000 - 50000)/4. I choose midk like this because it will take 16 times longer to PRP test k=200000 than k=50000. midk is about 3/4 of the range about lowk.

Run PRP/LLR/PFGW on midk*base^n+/-1 doing about 10% of the PRP test.

Multiply the time it took to do 10% by 10.

Use that time to be the breakpoint to change over from sieving to PRP testing.

I'm certain that others have different methods.

Use that time
rogue is offline   Reply With Quote