[QUOTE=R.D. Silverman;102484]Here is 3,2,403- C151 = p45.p106

987181561950506928972744054925015604731086073

1347554579979565353610087203935075781206952880101757908044334156103650470019517487990193757517800438110043


I am running the linear algebra for 6,5,229+ now.

I have acquired access to a small number of machines. It's not much
(about 6) but it should be enough to let me work on the smaller
Cunningham composites. I am therefore stopping work on these numbers
for the time being. I will next do 5,423+.[/QUOTE]

Here is 6,5,229+ C153

20934053594010155436854727673276656428254127843897357129545565226269
16667756268390930507423505513279925983385385116782870468080394447151399720907474145003

I am returning to working on the Cunningham numbers

Updated tables
 

I've just uploaded the latest tables to the Web. There are now only 102 composites remaining and the ECMNET server is roughly 2/3 of the way through having run a p40 test on the entire set of composites.

Well done to everyone who sent in factors since the last update almost three weeks ago, and best of luck in finding more.


Paul

Another update has now been posted. If my counts are correct, 18 new factors were sent in by a variety of contributors and there are now 87 composites remaining in the tables.

The ECMNET server is now most of the way through handing out tasks with B1=3M and is finding factors of 40 digits or more.

When a the number of composites falls to 50 or fewer I'll add some extensions to the tables. Some of the added numbers will doubtless have small factors to be found.


Paul

[QUOTE=xilman;104106]Another update has now been posted. If my counts are correct, 18 new factors were sent in by a variety of contributors and there are now 87 composites remaining in the tables.

The ECMNET server is now most of the way through handing out tasks with B1=3M and is finding factors of 40 digits or more.

When a the number of composites falls to 50 or fewer I'll add some extensions to the tables. Some of the added numbers will doubtless have small factors to be found.


Paul[/QUOTE]


I find it interesting that only one result was found by ECM.

[QUOTE=R.D. Silverman;104113]I find it interesting that only one result was found by ECM.[/QUOTE]That factor was the smallest of the bunch and a p43. The next smallest was also p43, and the third was p45. Only six are under p50. The ECMNET server is handing out tasks optimized for finding p40 factors.

I believe there are very few factors under p45 remaining to be found and so relatively few of any size will be found with ECM before I extend the tables.

On the other hand, there are still many factorizations which are relatively straightforward by NFS and those who choose this algorithm will be rewarded with factors.


Paul

4,3,337+
 

This was about 3 weeks ago, for 4,3,337+:

C134 = C67.C68 using GNFS
C67 = 7235190328551470741532048196017244937179206678641778090829662010159
C68 = 11293028812494330707113597880393770802635862401973530748584876099459

Both factors were 223 bits :whistle: :flex:

Thanks to Sander for sending me the singleton-pruning scripts -- a big, big help.

Currently dead in the water on 6,5,247+. Built 5 matrices, with lower and lower weights, only to see the sqrt fail every time. I knew that the ggnfs sqrt dislikes sextics, but not this much. I may go straight at this one with a quintic.

Currently working on 4,3,331- (GNFS) and 4,3,337- (SNFS).

[QUOTE=FactorEyes;104146]T

Currently dead in the water on 6,5,247+. Built 5 matrices, with lower and lower weights, only to see the sqrt fail every time. I knew that the ggnfs sqrt dislikes sextics, but not this much. I may go straight at this one with a quintic.

Currently working on 4,3,331- (GNFS) and 4,3,337- (SNFS).[/QUOTE]

The latest msieve 1.19 can complete these factorizations. You may need to increase the limits on the size of the inputs. In include/mp.h, increase MAX_MP_WORDS to 24, and in common/expr_eval.c increase the limit on line 390, then recompile with make nfs. Put just the number in worktodo.txt, create msieve.fb with the format

[CODE]N <number>
R0 -22452257707354557240087211123792674816
R1 3552713678800500929355621337890625
A0 6
A1 0
A2 0
A3 0
A4 0
A5 5
A6 5

FRMAX 8200000
FAMAX 8200000

[/CODE]
filling in the appropriate poly and fb limits, create msieve.dat whose first line is N <number>, and the remaining lines are the relations, then start it with msieve -nc -v.

It currently requires more relations than GGNFS, so you may have to do a little more sieving, but that'll be faster than restarting with a quintic.

Greg

@Xilman: Have you recieved my email and my PM about [URL="http://www.mersenneforum.org/showpost.php?p=104558&postcount=66"]this factorization[/URL] (about two weeks ago)? I have neither got an answer, nor do I see any update in your [URL="http://www.leyland.vispa.com/numth/factorization/anbn/UPDATE.txt"]Homogeneous Cunningham Numbers file[/URL], so maybe the email may have got stuck in your Spam filter?

[QUOTE=Andi47;105812]@Xilman: Have you recieved my email and my PM about [URL="http://www.mersenneforum.org/showpost.php?p=104558&postcount=66"]this factorization[/URL] (about two weeks ago)? I have neither got an answer, nor do I see any update in your [URL="http://www.leyland.vispa.com/numth/factorization/anbn/UPDATE.txt"]Homogeneous Cunningham Numbers file[/URL], so maybe the email may have got stuck in your Spam filter?[/QUOTE]Apologies for not responding earlier.

I did receive it but have yet to do anything with it or with several other factorizations. With luck, there may be an update posted this weekend.

I've not been having a good time for the last 6 weeks and many things have slipped. Details may appear later in the Unhappy Me thread.


Paul

[QUOTE=FactorEyes;104146]This was about 3 weeks ago, for 4,3,337+:

C134 = C67.C68 using GNFS
C67 = 7235190328551470741532048196017244937179206678641778090829662010159
C68 = 11293028812494330707113597880393770802635862401973530748584876099459
[/QUOTE]

Can I reserve these 2 Composite numbers?
I am making sense?

Thank you

Sorry for the above post ... these numbers did not factor:rolleyes: