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New Mersenne Prime discovered (probably)

(www.mersenne.org)
359 points sdsykes | 5 comments | 16 Oct 24 11:51 UTC | HN request time: 0s | source
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dooglius ◴[18 Oct 24 23:59 UTC] No.41884540[source]▶
Why don't they say what it is?
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lifthrasiir ◴[19 Oct 24 00:15 UTC] No.41884602[source]▶
Because the EFF Cooperative Computing Awards for the first discovery of large enough prime numbers are still active. Publishing the probable prime in advance would risk someone verifying faster than GIMPS.
replies(3): >>41884609 #>>41884773 #>>41886873 #
Dylan16807 ◴[19 Oct 24 00:17 UTC] No.41884609[source]▶
It's hard to see how that someone would count as the discoverer.
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1. lifthrasiir ◴[19 Oct 24 00:19 UTC] No.41884617[source]▶
That someone will totally count as the discoverer under the current rules [1], because it requires the deterministic primality proof for given number. It doesn't matter how much effort was taken to reach that candidate so far, even though it would be virtually impossible to find any new prime without that. I think the temporary embargo is fully justified for this reason.

(And I think it is technically possible to probe the reports to find what it was anyway, but it is not easy to find one at least for me. If you are really looking for that, look for the P-PRP result type.)

[1] https://www.eff.org/awards/coop/rules

replies(1): >>41884735 #
2. phkahler ◴[19 Oct 24 00:45 UTC] No.41884735[source]▶
Is there a probabilistic test for Mersene primes? I thought they just wanted confirmation via independent calculation.
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3. lifthrasiir ◴[19 Oct 24 00:53 UTC] No.41884779[source]▶
Any probabilistic primality test will work, but GIMPS currently uses the first-time Fermat probable prime test with a very robust certificate [1] to filter almost all non-primes in advance.

[1] https://www.mersenne.org/various/math.php#prp

4. ◴[19 Oct 24 03:45 UTC] No.41885497[source]▶
5. af3d ◴[21 Oct 24 20:08 UTC] No.41908005[source]▶
It's called the "Lucas–Lehmer primality test". Without it, GIMPS probably wouldn't have found a single one of them in an acceptable amount of time. The one that was just discovered is HUGE. I had to write a program just to slow down the output enough to be able to appreciate its shear magnitude (it is still printing as I write this!).