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Old 2013-02-17, 12:40   #1
Arkadiusz
 
Dec 2009

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Exclamation PFGW can't find a small factor.

For example,
2362339121*2^1018-1 has no small factor.

mod(2362339121*2^1018-1, 17) = 0.
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Old 2013-02-18, 00:19   #2
rogue
 
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Quote:
Originally Posted by Arkadiusz View Post
For example,
2362339121*2^1018-1 has no small factor.

mod(2362339121*2^1018-1, 17) = 0.
Thanks. I will investigate.
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Old 2013-02-18, 04:01   #3
axn
 
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Quote:
Originally Posted by Arkadiusz View Post
For example,
2362339121*2^1018-1 has no small factor.

mod(2362339121*2^1018-1, 17) = 0.
What version?

Code:
PFGW Version 3.6.0.32BIT.20111222.Win_Dev [GWNUM 26.6]

2362339121*2^1018-1 has factors: 17
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Old 2013-02-18, 04:07   #4
Batalov
 
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Code:
PFGW Version 3.7.2.64BIT.20130122.x86_Dev [GWNUM 27.9]
2362339121*2^1018-1 is composite: RES64: [3DE9C23DFB42D757] (0.0017s+0.0267s)
...
PFGW Version 3.7.3.32BIT.20130210.Win_Dev [GWNUM 27.8]
2362339121*2^1018-1 is composite: RES64: [3DE9C23DFB42D757] (0.0022s+0.0838s)
PFGW Version 3.7.3.64BIT.20130210.Win_Dev [GWNUM 27.8]
2362339121*2^1018-1 is composite: RES64: [3DE9C23DFB42D757] (0.0020s+0.0295s)
- probably introduced later than 3.6.0

Last fiddled with by Batalov on 2013-02-18 at 04:12
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Old 2013-02-18, 07:42   #5
ET_
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What is the command line?

pfgw[32|64]{s} -q2362339121*2^1018-1

or

pfgw[32|64]{s} -t -q2362339121*2^1018-1

or

pfgw[32|64]{s} -t -f -q2362339121*2^1018-1

?

Luigi
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Old 2013-02-18, 08:25   #6
axn
 
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I used -f -q (in windows command line you have to escape the ^ with ^^)
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Old 2013-02-18, 10:23   #7
Arkadiusz
 
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Open WinPFGW Version 3.6.5.
PFGW Version 20130210.
pfgw -f -o input file.txt
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Old 2013-02-18, 12:43   #8
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3.6.7 finds the factor, but 3.7.3 does not. I assume it was due to reintroduction of the tree factoring code. I'm getting help from someone much more familiar with that code.
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