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Old 2006-03-03, 05:27   #221
Kosmaj
 
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grobie
Congrats on a nice prime! It's the best to counter false primes with real ones!

As for the composite by Thomas, let's hope it was a typo.
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Old 2006-03-03, 10:14   #222
Thomas11
 
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Default no typo!

Quote:
Originally Posted by Kosmaj
As for the composite by Thomas, let's hope it was a typo.
Sorry, Kosmaj, but it wasn't a typo!

Code:
151*2^413621-1 is not prime.  LLR Res64: 2485F228CAD65A7C  Time : 490.694 sec.
151*2^413655-1 is not prime.  LLR Res64: 6A9B2115DEC44054  Time : 490.661 sec.
151*2^413669-1 is not prime.  LLR Res64: B2C573C33600C176  Time : 490.657 sec.
151*2^413705-1 is not prime.  LLR Res64: F85D273D726BCAF7  Time : 490.840 sec.
151*2^413825-1 is not prime.  LLR Res64: 02F7C33D065FC367  Time : 490.719 sec.
151*2^413933-1 is prime!  Time : 490.991 sec.
151*2^413969-1 is not prime.  LLR Res64: FBB6B1A7DAEFF386  Time : 491.058 sec.
151*2^413993-1 is not prime.  LLR Res64: FE0D93A9A1C09A6C  Time : 491.130 sec.
151*2^414113-1 is not prime.  LLR Res64: E2A1F1EDDFBACC95  Time : 493.733 sec.
151*2^414215-1 is not prime.  LLR Res64: D6B6E1417E929D50  Time : 491.800 sec.
151*2^414221-1 is not prime.  LLR Res64: ADB287529B1B4171  Time : 493.508 sec.
After I've got noticed about the non-primality, I did a verification run on the same machine (AthlonXP 2400+ @ 2GHz, 512 MB, Windows 2000, LLR 3.6.2):

Code:
151*2^413933-1 is not prime.  LLR Res64: 8440059416AD03E7  Time : 492.292 sec.
I'll do another verification run on a Linux P4 for a few of the other candidates, to see if the residues match.

I should add that I never had any problems on this machine. I'm using it for about 3 years now for finding quite a lot of "true" primes...

Seems, that this problem isn't restricted to grobie's machine.
And it doesn't seem to be SSE2 related, since on the Athlon LLR uses the non-SSE2 code.


Last fiddled with by Thomas11 on 2006-03-03 at 10:16
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Old 2006-03-03, 19:58   #223
lsoule
 
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1694614845*2^315949-1 (95120 digits)
(confirmed PRP with pfgw )
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Old 2006-03-04, 14:51   #224
Thomas11
 
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Another pair of primes:
155*2^310312-1 (93416 digits)
155*2^310622-1 (93509 digits)

I verified them on a second machine, let's see Chris Caldwell's final check...
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Old 2006-03-04, 15:23   #225
Kosmaj
 
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They were just confirmed to be primes.

A nice pair of neigbours, congrats!
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Old 2006-03-04, 21:55   #226
Flatlander
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125*2^418034-1 is prime.
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Old 2006-03-04, 22:05   #227
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199*2^263051-1 is prime!
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Old 2006-03-05, 01:14   #228
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From choose your own k
22932195*2^437820-1 (131805 digits)
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Old 2006-03-05, 12:05   #229
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93*2^362268-1 is prime!
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Old 2006-03-06, 09:37   #230
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155*2^353384-1 (106382 digits)
155*2^374288-1 (112675 digits)
155*2^496604-1 (149495 digits)
161*2^371426-1 (111813 digits)

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Old 2006-03-06, 11:01   #231
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Nice primes Thomas! k=155 is so prolific but not so high weight, for example less then k=23 which has just a few primes.
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