Yes, the probability is between 0.9 and 1.2%

I've been thinking about P-1 on SoB. Unlike GIMPS, the number of PRP tests saved if a factor is found is not clear. It all depends on how far behind double-checking is and when you think a prime will be found that will stop the double-checking effort.

I've just changed prime95 so that it takes a floating point value for how-far-factored. The last argument is no longer a double-check flag it is a floating point value representing the number of PRP tests that will be saved if a factor is found.

Furthermore, since SoB does not have enough P-1 clients, is it better to do more exponents at a 1.0 (or less?) PRP tests saved setting or fewer exponents at a higher PRP tests saved setting? I don't know. My gut reaction says it doesn't matter. The difference in efficiency is likely to be very, very slight.

I'll try to upload the new prime95 in the next day or two.