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Old 2005-04-09, 10:31   #23
axn
 
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For n=82, there are 4 k's < 10^12

42290329515
481562533725
549711786105
624949113615

EDIT: No luck for n=81 for k < 10^12. This n was a "low weight" one compared to n=82

Last fiddled with by axn on 2005-04-09 at 10:41
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Old 2005-04-09, 13:59   #24
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No luck for n=100,101,102.

@axn1 What OS are you using for your siever programm.
If it is windows is it possible that i can download it somewhere?

Lars
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Old 2005-04-09, 14:34   #25
robert44444uk
 
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Default no luck either

I did n=110 last night to k=10^11, no octoproths thier either

Regards

Robert Smith
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Old 2005-04-10, 08:46   #26
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Checked 109 last night, one candidate that fell at the last hurdle, unlike the horse I chose for the Grand National, which cost me a tenner when it fell at the first!

Will do 108 tonight.

Regards

Robert Smith
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Old 2005-04-11, 02:51   #27
TTn
 

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Robert,

Nice find, I will have to check it out.
I have been touching up RMA a bit, and have'nt been online to catch up on what's going on.

TTn
 
Old 2005-04-11, 09:04   #28
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Results for n = 97 (after 65% completion to k<10^13)

1926973493115
2212009461375
2412877121565
5647136892825

@ltd - see the attached Pascal source code - Its not much. You'll have to modify the constants in the program and compile (you can use FreePascal compiler).

I plan to later clean it up and make it accept command line parameters
Attached Files
File Type: txt octo.pas.txt (2.3 KB, 165 views)

Last fiddled with by axn on 2005-04-11 at 09:05
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Old 2005-04-11, 09:43   #29
ET_
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Quote:
Originally Posted by axn1
Results for n = 97 (after 65% completion to k<10^13)

1926973493115
2212009461375
2412877121565
5647136892825

@ltd - see the attached Pascal source code - Its not much. You'll have to modify the constants in the program and compile (you can use FreePascal compiler).

I plan to later clean it up and make it accept command line parameters
May I ask you which boost of performance gave the substitution of Pascal code with asm code?

Luigi
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Old 2005-04-11, 10:11   #30
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Quote:
Originally Posted by ET_
May I ask you which boost of performance gave the substitution of Pascal code with asm code?

Luigi
The two divisions in TestK - gave appr. 35% speedup. Not much but I'll take any speedup especially since I am running these for 2-3 days at a stretch. Actually, there is one more optimization there - the division of k by p is done by two back-to-back divisions; for most cases you only need one division. I plan to code it up and try it out. Let's see what kind of improvement it brings. For people needing non-asm version, you can use suitable qword operations. But in such cases, it might be worthwhile to use alternatives to division.
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Old 2005-04-11, 11:38   #31
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Quote:
Originally Posted by axn1
Results for n = 97 (after 65% completion to k<10^13)

1926973493115
2212009461375
2412877121565
5647136892825
One more to the list for n = 97

6832047128535
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Old 2005-04-11, 13:01   #32
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Uploading the latest version of the sieve along with the executable. The output needs to be redirected to some file. The resulting file can be further sieved using NewPGen.
Attached Files
File Type: zip octo.zip (13.2 KB, 158 views)
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Old 2005-04-11, 13:09   #33
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Default 108

Ran 108 last night to 10^11, and no octos, sadly to say.

Axn1, will you be writing your code in a windows executable? I would certainly be interesting in devoting some raw computer power to take it further.

Regards

Robert Smith
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