[QUOTE=hyramgraff;477295]
C891 = P24 * C868 [url]http://factordb.com/index.php?id=1100000000685534226[/url]
[/QUOTE]

Oops, that wasn't a C868 it's a [B]PRP868[/B].

[QUOTE=hyramgraff;477302]Oops, that wasn't a C868 it's a [B]PRP868[/B].[/QUOTE]Very nice!

VBCurtis, thanks for explaining generally how the siever is used. I had a play around with some of the settings, and it's something that might be useful in the future if I have a composite that's near one of the boundaries.

Reserving these now:
[CODE] Number File Remainder
[URL="http://www.factordb.com/index.php?query=%2817312814599396059%5E13-1%29%2F17312814599396058"]17312814599396059^13-1[/URL] t1200 c147
[URL="http://www.factordb.com/index.php?query=%2819321617196953199%5E13-1%29%2F19321617196953198"]19321617196953199^13-1[/URL] t1000 c160
[URL="http://www.factordb.com/index.php?query=%2833565630407553129%5E13-1%29%2F33565630407553128"]33565630407553129^13-1[/URL] t800 c145
[URL="http://www.factordb.com/index.php?query=%2837921183808153449%5E13-1%29%2F37921183808153448"]37921183808153449^13-1[/URL] t1200 c165
[URL="http://www.factordb.com/index.php?query=%2839383509906716221%5E13-1%29%2F39383509906716220"]39383509906716221^13-1[/URL] t800 c173
[URL="http://www.factordb.com/index.php?query=%2878372732118311223%5E13-1%29%2F78372732118311222"]78372732118311223^13-1[/URL] t800 c172[/CODE]

I've actually already completed the first and found a p41 * p53 * p54. Obviously the p41 could have been found with ECM, but would it have been worth running ECM to that level? I'm not sure what's optimal as SNFS only took 39 hours on a 3.4 GHz quad core. (And of course, I've no idea what ECM work has already been carried out.)

As I am loathe to duplicate work, or otherwise waste time, I think I will stay away from the t1000+ files after my current reservation.

[QUOTE=hyramgraff;477302]Oops, that wasn't a C868 it's a [B]PRP868[/B].[/QUOTE]Now it's a p868. :smile:

[QUOTE=lavalamp;477305]Now it's a p868. :smile:[/QUOTE]

Thanks!

I'm continuing to run 20 digit ECM on the t2100 file.

C899 = P25 * C875 [url]http://factordb.com/index.php?id=1100000000685534562[/url]

C901 = P24 * C877 [url]http://factordb.com/index.php?id=1100000000683471523[/url]

C905 = P22 * C883 [url]http://factordb.com/index.php?id=1100000000685534777[/url]

C970 = P25 * C945 [url]http://factordb.com/index.php?id=1100000000685535744[/url]

More results from the t2100 file have been added to factordb. I'm only including links for the interesting ones:

C519 = P10 * P12 * P18 * C482 [url]http://factordb.com/index.php?id=1100000001083380391[/url]
(Note: factordb is missing the factorization of a C253 for the parent number [url]http://factordb.com/index.php?id=1100000001086258467[/url])

C655 = P23 * C643

C676 = P23 * C653

C713 = P28 * C686

C717 = P27 * C691

C808 = P27 * C781

C809 = P27 * C783 [url]http://factordb.com/index.php?id=1100000000685524627[/url]

C809 = P27 * C783 [url]http://factordb.com/index.php?id=1100000000685524823[/url]

(Yes two numbers of the same length both had 27 digit factors.)

C810 = P26 * C785

C813 = P24 * C790

C815 = P22 * C793

C815 = P26 * C790

C817 = P22 * C795

C819 = P26 * C794

C820 = P21 * C800

C821 = P23 * C799

C821 = P20 * C801

C844 = P22 * C822

C846 = P21 * C825

C856 = P21 * C836

C856 = P28 * C829

C864 = P23 * C842

C867 = P24 * C843

C868 = P25 * [B]PRP843[/B] [url]http://factordb.com/index.php?id=1100000000685533041[/url]

C870 = P21 * C849

C910 = P22 * C888

C926 = P22 * C904

C924 = P25 * C924

My 20 digit ECM run on all the numbers in the t2100 file should finish by Monday. I'd like to do a quick pass on the mwrb2100 file next. Does anyone have a copy of the mwrb2100 file with the factored numbers removed?

Nice work [B]hyramgraff[/B]!!

The mwrb file is a collection of the Most Wanted. Because of that, many numbers have already had higher levels of B1 (ECM) tested. Though I don’t know the specifics, I would assume they are tested to the t50 or better levels.

If you haven’t noticed the factored numbers are either removed from or the composites reduced in the tXXX file within 24-48 hours. This shows the work done by you and others. I would suggest you go to higher levels if you have the resources to do so.

In case anyone else is like me and prefers to search by exponent, I have sorted the t550 and t600 files this way. SNFS difficulty range is given before each exponent block.

Sadly there's nothing in the 100's for SNFS difficulty, but there's plenty in the low 200's available, even in the t550 file.

[QUOTE=lavalamp;477503]In case anyone else is like me and prefers to search by exponent, I have sorted the t550 and t600 files this way. SNFS difficulty range is given before each exponent block.

Sadly there's nothing in the 100's for SNFS difficulty, but there's plenty in the low 200's available, even in the t550 file.[/QUOTE]

This is the area I have been working. Generally speaking, if the remaining composite is less than C194 and the SNFS difficulty is under 230, then it is ready for SNFS. They have been fully ECMed. Some of the smaller composites are more suited for GNFS but not all those are fully ECMed.

Not sure why you mentioned degree 6 for a "<base> 10" number. The best polynomial is the degree halving one of:
[CODE]skew: 1.00
c5: 1
c4: 1
c3: -4
c2: -3
c1: 3
c0: 1
Y1: -<base>
Y0: <base>^2+1[/CODE]
Likewise with "<base> 12".

Earlier I was referring to using degree halving for p^17-1 as an octic.

[QUOTE=RichD;477512]Not sure why you mentioned degree 6 for a "<base> 10" number.[/QUOTE]I did also give SNFS difficulty for the degree 5 poly. my thinking at the time was that perhaps the degree 5 wouldn't be optimal at that size, but on reflection it would still probably be better than a much higher difficulty degree 6.

That said, I didn't include degree 6 SNFS difficulty in the t550 file, so go figure. ¯\_(ツ)_/¯

For the "<base> 16" numbers, I included both degree 6 and degree 8 polynomial difficulties, but based on recent experience I don't think the degree 8 poly from degree halving is preferable.

t550/t600 files
 

Namely, the following are available and ready for SNFS.
If anyone wants to tackles these, help yourself.
[CODE]14020072124657538094183043839811142289 6
5713839242138307627889538424597962861 6
11658852700685942029849 10
6721393100152677634549 10
1339322446256468156596004408950229501 6
2959025653654433029 12
27945714132675033142899109225439212386442031501005140283 4
98811777493935291929249 10
1943777054011345723 12[/CODE]