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Old 2008-08-24, 12:01   #23
Mini-Geek
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But he's not around this time, so maybe the algorithm was used on the real M45 (unless he set up a script to swap it with a different one from the same period and use the algorithm on that one). Um...what is the algorithm, anyway?
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Old 2008-08-24, 12:10   #24
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Quote:
Originally Posted by Mini-Geek View Post
Um...what is the algorithm, anyway?
Learning the fake algorithm is part of the initiation procedure for entering the inner sanctums of GIMPS. You have to fill out an application form and be vetted by established priest-members. Be sure to bring six raccoon pelts (obtainable from your local raccoonnookkeeper).

Last fiddled with by cheesehead on 2008-08-24 at 12:14
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Old 2008-08-24, 12:51   #25
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Quote:
Originally Posted by Mini-Geek View Post
But he's not around this time, so maybe the algorithm was used on the real M45
This is what I answered by saying I can't find any residue following the fake algorithm in the exponents in cleared yesterday between 10am and 7pm UTC, so it seems there is a new algorithm that automatically makes a new fake residue, or just takes a random 64bit number.

The algorithm was posted here in #30:
http://www.mersenneforum.org/showthread.php?t=1508

But its much easier than it looks if you look at 29225803 and 0xB6C80136DB7FED__.

If you look at the exponent in binary: 1101111011111001101001011

First you take mod 16, which is the last 4 binary digits 1011 or B in hex, then you move 1 place right and add zeros so next is 0110 or 6 in hex, next is 1100 or C in hex, next is 1000 or 8 in hex and next is 0000 or 0 in hex.

Now the algorithm involves (p >> 28) which is p in binary moved 28 places right, we now start from the beginning with zeros padded in front of exponent (I can make a longer explanation if anyone wants, but this is just a rule of thumb):
First we get 0001or 1 in hex, then 0011 or 3 in hex, then 0110 or 6 in hex, then 1101 or D in hex, then 1011 or B in hex, then 0111 or 7 in hex, then 1111 or F in hex, then 1110 or E in hex, then 1101 or D in hex, and now we got entire residue: B6C80136DB7FED.

Last fiddled with by ATH on 2008-08-24 at 12:53
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Old 2008-08-24, 16:29   #26
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Has the verification run started yet? Or do we have to wait until George gets back?
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Old 2008-08-24, 17:34   #27
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Quote:
Originally Posted by ixfd64 View Post
Has the verification run started yet? Or do we have to wait until George gets back?
Considering an Intel quad core like one in the benchmark thread can test 29225803 in under 5 days, why doesn't someone just verify it themselves?
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Old 2008-08-24, 17:38   #28
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Quote:
Originally Posted by Mini-Geek View Post
Considering an Intel quad core like one in the benchmark thread can test 29225803 in under 5 days, why doesn't someone just verify it themselves?
I guess the main reason being that no one here actually knows what the number is (or at least no one is saying if they do know). That kinda puts a stopper on testing it.
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Old 2008-08-24, 17:56   #29
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Quote:
Originally Posted by Mini-Geek View Post
Considering an Intel quad core like one in the benchmark thread can test 29225803 in under 5 days, why doesn't someone just verify it themselves?
ATH wasn't saying that 29225803 was the exponent.
I'm not sure how his interpretation of the fake residue algorithm would
apply to 26 bit exponents either. I can't quite understand or reconcile it with the
pseudocode in the link either.

Last fiddled with by davieddy on 2008-08-24 at 17:58
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Old 2008-08-24, 21:40   #30
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My encrypted M45 guess is 855E7A77. I'll say that it was reported in the 7:00 hour.
Its residue perfectly matches the fake residue calculator. Anybody that's read the last few posts and looks at the cleared.txt file will be able to find the same number, but to prevent spreading quite possibly false rumors about M45, I'll just leave it at this.
I find it unlikely that the fake residue was swapped, since there were no people here this time to swap it.
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Old 2008-08-24, 22:19   #31
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Quote:
Originally Posted by Mini-Geek View Post
My encrypted M45 guess is 855E7A77. I'll say that it was reported in the 7:00 hour.
Its residue perfectly matches the fake residue calculator. Anybody that's read the last few posts and looks at the cleared.txt file will be able to find the same number, but to prevent spreading quite possibly false rumors about M45, I'll just leave it at this.
I find it unlikely that the fake residue was swapped, since there were no people here this time to swap it.
By George he's right. Thanks for the heads-up. Should I start doing a DC? Or is that being too interfering?

This new number just goes to show how unpredictable these prime really are!

Last fiddled with by retina on 2008-08-24 at 22:29
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Old 2008-08-24, 22:28   #32
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Wow!

It's less than M44!

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Old 2008-08-24, 23:10   #33
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Yeah nice. I missed it cause I didn't look back far enough, and I was sure they stopped using that algorithm.
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