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Old 2009-03-20, 07:25   #1
schickel
 
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"Frank <^>"
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Default Aliquot ranges and status

As of August 2011, all sequences with a starting number below 1000000 have been calculated to a minimum height of 110 digits (some may have dropped back below that size due to recent downdriver activity), and there are 9253 open sequences in that range.

We are, I believe, the largest project right now that is actively pursuing sequences throughout the entire range. Any open ended sequence is available for reservation, with the following possible exceptions:

The Lehmer Five, 276, 552, 564, 660, & 966, along with 1074, 1134, 19560 & 204828 are currently maintained by Paul Zimmermann. Please co-ordinate any work with him.

The 74 sequences from 1200-10000, with the exception of 4788, are maintained by Christophe Clavier and associates. Email Christophe Clavier to reserve these.

4788 is currently reserved as a team project by the members of Mersenneforum. Its primary interest is due to work originally done by Wieb Bosma. His work showed a merge occuring after an extensive run. Further investigation by Clifford Stern showed that it actually merges with 4788 rather than 16100. Since the merge occurs after 6400+ lines, the combined sequence pair 314718/4788 is the longest open sequence at 9000+ lines. Fortunately, stability was achieved at line 2470 and 171 digits with the loss of the '3' factor, eventually followed by a short downdriver run. Stability has now been reached again at 166 digits. Check the 4788 thread for the latest info.

Sequences in the range 10116-99840 are of particular interest to Clifford Stern. This range has been completed to a minimum of 110 digits by the forum, with selected sequences being pursued higher by Clifford. If you wish to work in this range, check with Clifford, he may have completed work that has not been uploaded to the Factoring Database yet. Most sequences that he is working will be called out in the reservation thread here.

1000000-4000000 has been completed up to 71 digits by axn. Currently there is no active project working above 1000000.

Everything else is open for pursuit. Check the reservation thread for current reservations before embarking on any large-scale effort. Links to sites with more in-depth information are available here.

Advice and help on getting started with Aliquot Sequences are available here, just post any questions or problems you might have.

Advice and help on getting started with large-scale factoring efforts are available over in the Factoring Forum.

Last fiddled with by 10metreh on 2012-08-08 at 18:47 Reason: PaulZ is now working 19560 as well
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Old 2009-03-24, 14:28   #2
akruppa
 
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I just asked Paul about the sequences he maintains. He mentioned that some time ago, he was looking for someone that could run a web-based interface to give access to these sequences with the option of submitting new factors so the sequence would be updated automatically. Does someone operate a web page like this? Maybe even with ECMNet server attached or some such? He'd transfer these 8 sequences then.

Alex
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Old 2009-03-24, 16:16   #3
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Except for the ECMNet part, that describes Syd's database, http://factorization.ath.cx/search.php. The database understands ELF format for the bulk submission of factors, not Paul's fmt format, but I'll be happy to convert them and submit the sequences.

Greg
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Old 2009-03-24, 16:48   #4
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Quote:
Originally Posted by frmky View Post
Except for the ECMNet part, that describes Syd's database, http://factorization.ath.cx/search.php. The database understands ELF format for the bulk submission of factors, not Paul's fmt format, but I'll be happy to convert them and submit the sequences.

Greg
Does the database check for integrity? (sometimes aliquot.ub finds nonsense factors due to a bug either in ubasic or in the script.)
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Old 2009-03-24, 16:55   #5
Syd
 
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Quote:
Originally Posted by Andi47 View Post
Does the database check for integrity? (sometimes aliquot.ub finds nonsense factors due to a bug either in ubasic or in the script.)
It does, nonsense factors are simply ignored.
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Old 2009-03-24, 17:48   #6
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Quote:
Originally Posted by Syd View Post
It does, nonsense factors are simply ignored.
Are lines which follow nonsense factors (and are therefore nonsense too) ignored too?
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Old 2009-03-24, 18:02   #7
Syd
 
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Quote:
Originally Posted by Andi47 View Post
Are lines which follow nonsense factors (and are therefore nonsense too) ignored too?
No they are imported, but taken as another sequence starting with the first nonsense result, therefore it wont show up unless you request it.
There is also no need to submit the sequences in order, you can start for example with lines 2000 to x and submit the first 2000 lines later, even mix the whole sequence up, mix it with another one, leave out the index numbers, etc.
In most cases it recovers the sequences from it.

Last fiddled with by Syd on 2009-03-24 at 18:05
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Old 2009-03-24, 19:02   #8
mklasson
 
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Quote:
Originally Posted by Syd View Post
No they are imported, but taken as another sequence starting with the first nonsense result, therefore it wont show up unless you request it.
There is also no need to submit the sequences in order, you can start for example with lines 2000 to x and submit the first 2000 lines later, even mix the whole sequence up, mix it with another one, leave out the index numbers, etc.
In most cases it recovers the sequences from it.
This is very neat Syd! Now when are you going to add a "reserve sequence" feature?
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Old 2009-03-25, 08:44   #9
schickel
 
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Quote:
Originally Posted by akruppa View Post
I just asked Paul about the sequences he maintains. He mentioned that some time ago, he was looking for someone that could run a web-based interface to give access to these sequences with the option of submitting new factors so the sequence would be updated automatically. Does someone operate a web page like this? Maybe even with ECMNet server attached or some such? He'd transfer these 8 sequences then.

Alex
I have some ideas I'm considering on building that exact type of system. I'll have to see how much spare time I can come up with this year. With the economy in the state it's in, this year looks to prove very, um, interesting at work.....

With the upsurge in interest here lately, I'd like to get something built in the not too distant future to take advantage of all the energy.
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Old 2009-07-13, 02:03   #10
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Default Updating database

Quote:
Originally Posted by schickel View Post
10,000-100,000 maintained by Clifford Stern. He maintains records of downdriver runs among other type of records.
How do we get this info into the database?

Do we have to recreate the work for each index?

I am willing to volunteer to help import the data if it is freely available.

RichD.
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Old 2009-07-13, 02:22   #11
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The database does have toubles with squares over 2000, so I have had troubles with terms like 3701^2 for example (if 3701 is prime that is).

If you find your sequence you just added has a small term of 7-12 digits that didn't factor, then you may have to manually find the square root. Because of the feature Syd mentioned, once you fix the square root issue, your whole sequence shows up.
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