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Message boards : Sophie Germain Prime Search : First prime (the 2nd)

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Bur
Volunteer tester

Joined: 25 Feb 20
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Message 140587 - Posted: 3 Jun 2020 | 18:01:44 UTC

I couldn't reply in the old thread, probably due to it being old. So here's a new one.

After just 7000 WUs I noticed a task taking close to 4000 s and after a few hours received a mail saying I found a prime. Something like 350,000 digits, so noting special, but since it's the frist I found, I was somewhat excited. :D

I have a question though, were the tests for twin prime and SG prime already done? Or will that be a seperate WU? In other words, can I keep my fingers crossed?

And maybe it's of use to some others, I was tracking the probability for finding a prime. This can be done by p = 1-(1-1/x)^n where x is the number of WUs it takes to find a prime (you can get this from the stats page, right now it's something like x = 14450 for SGS) and n is the number of tasks one has processed so far.

So finding one after only 7000 tasks has a 39% chance, combined with me finishing 1st only in about 45% of all WUs, this had a 17% chance to happen so soon. So even if it's not a special prime, I'm still feeling lucky. ;)

JeppeSN

Joined: 5 Apr 14
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Message 140588 - Posted: 3 Jun 2020 | 18:12:52 UTC

No need to keep fingers crossed. The prime shows up on your account (when I click your name here in the forum) already, so it does not have any "companion".

The fact that it has no twin was established by your own work, which is why this task took longer than ordinary tasks in this project.

The fact that it is not Sophie Germain (or safe, although the current sieve does not give a good chance for safe primes) was established by the server already.

/JeppeSN

Eudy Silva

Joined: 26 Aug 17
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Message 140590 - Posted: 3 Jun 2020 | 19:03:46 UTC

Congrats, Bur !
____________
"Accidit in puncto, quod non contingit in anno."
Something that does not occur in a year may, perchance, happen in a moment.

Message boards : Sophie Germain Prime Search : First prime (the 2nd)