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Old 2014-07-20, 19:08   #1
houding
 
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Default Are factors vitrified?

I think I have read about this somewhere within another post, but I'm not sure.

If a factor for exponent is found (either via TF, P-1 or ECM) and submitted, is this factor also verified? Just to make sure that this was not submitted by a chancer randomly pushing buttons, and that a potential MP might now never be tested?
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Old 2014-07-20, 19:50   #2
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Quote:
Originally Posted by houding View Post
I think I have read about this somewhere within another post, but I'm not sure.

If a factor for exponent is found (either via TF, P-1 or ECM) and submitted, is this factor also verified? Just to make sure that this was not submitted by a chancer randomly pushing buttons, and that a potential MP might now never be tested?
The answer: Try submitting a fake factor.
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Old 2014-07-20, 19:56   #3
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Yes, it is verified. Verifying a factor is very easy, so PrimeNet does it for all reported factors.

There are still some ways that a Mersenne prime could be missed by GIMPS indefinitely:
  1. People leaving fake LL results to get credit they didn't earn
  2. Bugs in Prime95, etc.
  3. Bugs in PrimeNet
The end problem in the most likely cases would be that GIMPS records incorrect LL residues as double-checked. A future triple-check on independent systems would catch this.

Fortunately, all of these are fairly low-risk in my opinion, since there are some safeguards and checks to prevent each.

Last fiddled with by Mini-Geek on 2014-07-20 at 19:58
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Old 2014-07-21, 01:22   #4
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Kracker has it right. It's actually worth trying out. Nothing bad happens; don't worry.

Even though the numbers are very big, there's no reason the math can't be done on them; it just takes longer. Dividing a 300-million digit number by some 40-digit number is just a bit of a longer process than dividing 15 by 3.

Primenet checks factors when they are submitted by manually checking them, i.e. dividing MXXX,XXX,XXX by the alleged factor, which again doesn't take long. The trial factoring software does this millions of times per second when you're looking.
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Old 2014-07-21, 01:54   #5
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Just yesterday morning I tested if primes are 'vilified' at primes.utm.edu
(by accident, really... lost a leading digit from a number's representation, resulting in six composites in a row: it was a Cunningham chain).

The result was predictable: not only the numbers were quickly discarded, but I also received a yellow card and was blocked from further submissions for a predefined timeout (36 hours). Harsh, but fair!

I don't think primenet will ban you by IP... maybe only after many willfully wrong results in a short period of time. One or two? probably not.
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Old 2014-07-21, 04:49   #6
houding
 
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After many willfully wrong results you will be "vilified"!

Did not notice my typo until now.

Last fiddled with by houding on 2014-07-21 at 04:50
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Old 2014-07-21, 05:18   #7
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(Some thread titles are occasionally tampered with, for a humorous effect.
Most likely, you did not make that typo.)
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Old 2014-07-21, 20:21   #8
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Notice that factors are now being vitrified. Better than being experimented on in vitro, I would imagine.
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