Thread: P-1 discussion
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Old 2007-03-25, 18:22   #1
AntonVrba's Avatar
Jun 2005

2·72 Posts

How does prime95 choose the B1 and B2 constants?
Can one read about how the todo file format is interpreted?

As an experiment I tried the P-1 factoring of Prime95
which I did not know it could do. With the data as given
Prime95 estimates a 5.6% chance of finding a factor
and takes about 205 seconds to complete -
so playing around with the to do file parameters and I
changed the the ...,33,1 to ...,23,2, Now Prime95 estimates
a 34% chance of finding a factor and after 1010 seconds
P-1 found a factor in stage #2, B1=40000, B2=700000.
1625879*2^1625879+1 has a factor: 500311388963
(this factor is not found with the ...,33,1 parameter)
but the next 5 exponents could not be factored.
end of experiment.

I have no idea what would be good B1 and B2 parameters,
Maybe somebody could advise, have i jumped the gun?
is P-1 testing done in progressive stages?

Last fiddled with by AntonVrba on 2007-03-25 at 18:27
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