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Old 2019-07-18, 04:27   #2
Romulan Interpreter
LaurV's Avatar
Jun 2011

22·7·11·29 Posts

No idea if you found a bug or not (never looked for these probability numbers, they have no practical use, we just know from experience that the probability to find a prime is quite small )

But... The probabilities can change on the fly if somebody reports more TF or some P-1 with larger bounds (not the case here, tho).

Also... This exponent had a P-1 of about 5% and it was TF to 76 bits, therefore the probability of LL turning it prime is something like 1 in over a million. I think the first number is the one which is wrong, and the last one is the correct one. But this is just "in the head" approximation, I didn't take the pencil, so I could be wrong.

Edit: mind that your worktodo does not contain information of how far factored, and pm1 bounds, etc, those are only known after contacting the server. A typical LL line look like: "Test=blahblahkeykey,332199017,79,1", which for example, tells me the TF level, and give a hint about P-1. But for PRP, you need to contact the server to know these things. So, from this point of view, it also makes sense that the second number is right.

The chance of your number to be prime does not depend on the PRP or LL, it depends mostly of the exponent size and how much work was already done on it, except the PRP or LL work you are currently doing. Progressing into the LL or PRP test does not change the chances of the number being prime.

Therefore don't be so sad, your chances to find a prime it is just very-very-very small

Last fiddled with by LaurV on 2019-07-18 at 04:42
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