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 2005-03-10, 23:28 #1 jasong     "Jason Goatcher" Mar 2005 5·701 Posts Time to prp equation 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.
2005-03-11, 00:49   #2
rogue

"Mark"
Apr 2003
Between here and the

171C16 Posts

Quote:
 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

2005-03-11, 03:30   #3
jasong

"Jason Goatcher"
Mar 2005

5×701 Posts

Quote:
 Originally Posted by rogue 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
I'm still trying to figure out these instructions(I'm sure they make sense, it's just that I haven't done anything but simple math for awhile).

Thanks, though.

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