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Old 2012-02-29, 02:18   #166
vaughan
 
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I'm having a problem with the PRPnetclient.exe

It started with an Intel E8400 Wolfdale CPU based system. Now it has occurred on an Intel Q8200 quad-core system also. Both are running Windows 7 Ultimate 64-bit edition. Both computers were happily running NPLB prpnet on port 2000. Now they throw a message "prpclient.exe has stopped working" and below this heading it says "A problem caused the program to stop working correctly. Windows will close the program and notify you if a solution is available." It doesn't. This occurs when the start batch file is initiated. On the quad only 2 of the cores crash, so it leaves 2 instances (in separate sub-directories as per Lennart's batch file) running.

I tried re-installing the client using the install batch file right over the top of the existing files. Didn't help.

I'm stuck. Any ideas?
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Old 2012-02-29, 02:27   #167
Lennart
 
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Quote:
Originally Posted by vaughan View Post
I'm having a problem with the PRPnetclient.exe

It started with an Intel E8400 Wolfdale CPU based system. Now it has occurred on an Intel Q8200 quad-core system also. Both are running Windows 7 Ultimate 64-bit edition. Both computers were happily running NPLB prpnet on port 2000. Now they throw a message "prpclient.exe has stopped working" and below this heading it says "A problem caused the program to stop working correctly. Windows will close the program and notify you if a solution is available." It doesn't. This occurs when the start batch file is initiated. On the quad only 2 of the cores crash, so it leaves 2 instances (in separate sub-directories as per Lennart's batch file) running.

I tried re-installing the client using the install batch file right over the top of the existing files. Didn't help.

I'm stuck. Any ideas?
Save the resultfiles in prpclient-# folder then delete all prpclient-# folders.

Run install # core then update # core then start and it should work.


This is only a fast way to get it running again. You don't have to save the resultfiles if you don't need them.

Lennart
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Old 2012-02-29, 06:56   #168
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Thanks Lennart, that worked for both machines.
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Old 2012-11-19, 13:55   #169
vaughan
 
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Question: Do all Prime Numbers occur next to a number divisible by 6?
Eg 17 is next to 18.
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Old 2012-11-19, 13:59   #170
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yep, 1 mod 6 , -1 mod 6 or 5 mod 6.

meaning a prime will be of tthe form (x*6) plus or minus one
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Old 2012-11-20, 08:47   #171
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Quote:
Originally Posted by vaughan View Post
Question: Do all Prime Numbers occur next to a number divisible by 6?
Eg 17 is next to 18.
No.
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Old 2012-11-20, 08:51   #172
LaurV
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Quote:
Originally Posted by jnml View Post
No.
the (only) exceptions are 2 and 3
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Old 2012-11-20, 15:46   #173
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Quote:
Originally Posted by LaurV View Post
the (only) exceptions are 2 and 3
I agree with you LaurV.

Anybody else able to add to the discussion?
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Old 2012-11-20, 23:14   #174
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just for giggles I tested the first 100,000 primes and this is true for
3 < prime <= 239737
However there is no discernible pattern for whether the mod6 'seed' is 1 above or 1 below.
I sent you the worksheet
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Old 2012-11-21, 00:21   #175
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There is no need to test. It can be easily proven that all primes > 3 must be either p==(1 mod 6) or p==(5 mod 6). Proof:

p==(0 mod 6) is always divisible by 2 and 3
p==(2 mod 6) is always divisible by 2
p==(3 mod 6) is always divisible by 3
p==(4 mod 6) is always divisible by 2

This leaves p==(1 mod 6) and p==(5 mod 6) as the only possible primes mod 6.
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Old 2012-11-21, 00:53   #176
Stargate38
 
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If you convert the primes into base-6, you'll notice that, except for 2 and 3, they all end in 1 or 5. That's easy proof.

Last fiddled with by Stargate38 on 2012-11-21 at 00:53
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