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2006-04-13, 16:09   #45
Andi47

Oct 2004
Austria

2·17·73 Posts

Quote:
 Originally Posted by Pascal Ochem The factors of the C111 from 3^372+2^372 are: 840497702349180597209469882198293789055301120886641 (pp51) 766974650561302741840583863816378225180158232426458907919137 (pp60) with ggnfs (pp=probable prime)
Both of them are prime - certified with Primo within less than a second.

2006-04-13, 19:26   #46
Andi47

Oct 2004
Austria

2·17·73 Posts

Quote:
 Originally Posted by Andreas Schinde Done 300 curves with B1=3e6, no factor found.
500 more curves on 3^379+2^379 with B1=3e6; no factor found.

 2006-04-14, 16:12 #47 Jushi     Sep 2005 UGent 6010 Posts I've done some more curves (these include the ones mentioned in my previous post) 3,2,343- (C136) 650@1e6, 2440@3e6 3,2,371- (C141) 2440@3e6 3,2,391- (C161) 650@1e6, 637@3e6 3,2,395- (C144) 650@1e6, 357@3e6
2006-04-14, 17:03   #48
R.D. Silverman

Nov 2003

3·2,473 Posts

Quote:
 Originally Posted by Jushi I've done some more curves (these include the ones mentioned in my previous post) 3,2,343- (C136) 650@1e6, 2440@3e6 3,2,371- (C141) 2440@3e6 3,2,391- (C161) 650@1e6, 637@3e6 3,2,395- (C144) 650@1e6, 357@3e6
I think it is interesting that no factors are turning up! I did not put
forth much effort to begin with!

2006-04-14, 21:20   #49
xilman
Bamboozled!

May 2003
Down not across

22·41·61 Posts

Quote:
 Originally Posted by xilman Got them, thanks. It will take me a little time to put them on the web as I need to convert your mail to separate files and then to write an HTML wrapper. I'll probably put a separate copy of the tables in my standard format too --- one designed to be easily parsed by people and by programs. When the page is ready I'll post the URL here. Paul
Ok, the bare minimum work has now been completed and the tables are available on this page: http://www.leyland.vispa.com/numth/f.../anbn/main.htm

The files there were sliced out of Bob's email with a Perl program and a small amount of HTML written to make them accessible. Any formatting problems within each file, and some do have a few oddities, were in Bob's original.

As time goes by I'll pretty up the tables and I'll make additions and corrections.

Paul

 2006-04-14, 22:53 #50 smh     "Sander" Oct 2002 52.345322,5.52471 4A516 Posts Both 12^n-11^n and 12^n+11^n have a bad URL. The plus side is easy to figure out though ;-) And no, i didn't try all links.
2006-04-15, 05:55   #51
schickel

"Frank <^>"
Dec 2004
CDP Janesville

2·1,061 Posts
Another factor.....

Hi all,
On the plus side:
Quote:
 394 (2) 99289.347671117.182870936735296723148317.C151
the c151 reduces to 2882649460898258949163943038200219853.c114.
Let me know if anyone starts NFS on it....

and I make the remaining composite for 388+ as a c173, not a c175.

Later,
Frank

2006-04-15, 09:23   #52
xilman
Bamboozled!

May 2003
Down not across

1000410 Posts

Quote:
 Originally Posted by smh Both 12^n-11^n and 12^n+11^n have a bad URL. The plus side is easy to figure out though ;-) And no, i didn't try all links.
Thanks for checking. I'm fixing the errors now and will upload the correct versions shortly. The 12+11 error was my fault. Building the table of links was tedious and I used Emacs to write a few prototypes which were then changed to reflect the filenames required. The prototype for 12+11 was copied from a line from the 5+b table and wasn't fully edited.

You'll find the reason for 12-11 (and 12-7 which had the same problem) amusing. As posted earlier, I used a Perl script to create all the files. Bob's original file has these lines in it:

Code:
TWELEVEMINUSSEVEN
/************************************************************************/
/*                                                                      */
/*                             N    N                                   */
/*                           12  - 7                                    */
/*                                                                      */
/************************************************************************/
N		FACTORS
...
TWELEVEMINUSELEVEN
/************************************************************************/
/*                                                                      */
/*                             N     N                                  */
/*                           12  - 11                                   */
/*                                                                      */
/************************************************************************/
N		FACTORS
and so, of course, the files were created with names "tweleveminus{s,el}even.txt". That typo is not easy to spot! It took me several attempts, including the use of diff(1), before seeing what was wrong.

If you find any other errors in the HTML, please let me know. I'm not collecting additions and corrections to the underlying data just yet.

Paul

 2006-04-15, 21:32 #53 Pascal Ochem     Apr 2006 89 Posts The prime factors of the c118 from 3^359-2^359: 23284083412463789154370394112968359671893 108749847312011828223918710127691057819413106581587374895309543503706154857981 using GMP-ECM 6.1-beta2 [powered by GMP 4.2] [ECM]
 2006-04-16, 09:47 #54 Jushi     Sep 2005 UGent 1111002 Posts Update 3,2,343- (C136) 650@1e6, 2440@3e6 3,2,365- (C132) 650@1e6, 11@3e6 3,2,371- (C141) 2440@3e6 3,2,391- (C161) 650@1e6, 1960@3e6 3,2,395- (C144) 650@1e6, 2212@3e6 No factors yet
2006-04-16, 14:26   #55
xilman
Bamboozled!

May 2003
Down not across

100111000101002 Posts

Quote:
 Originally Posted by xilman I'm not collecting additions and corrections to the underlying data just yet.
That's not entirely true any more. The program I have for maintaining my other tables needs modification to deal with the new tables. Debugging the modified version has thrown up some oddities in the 3-2 table as follows:

123 has 1472268396497 listed as a factor. It's a typo for 147226839649

157: the large factor is composite with factors 34316843565107624715057451342247 and 969330861796869994456492130438574359

203: the large factor is incorrect. The P60 factor is actually 135154741774875856294696475102949312848119651741929977617013 and I've no idea at present where Bob's version came from.

Rather than post a complete list for all tables, I'll leave those as a taster for the sorts of errors my code throws out. When all the tables have been preened I'll put the corrected versions on the web site.

Please keep posting other corrections and new factors in this thread. I'll harvest them as and when the corresponding tables are checked by my code.

Paul

Last fiddled with by xilman on 2006-04-16 at 21:14 Reason: Typo

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