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[gd_barnes]

I am now done with 233324. A very sad state of affairs. After it dropped from 106 to 8 digits, it acquired the horrific 2^3*3*5 driver and never let go. Final status:

233324, i=3391, sz 116, C109

The good news is that I was able to add 1432 indexes to this one.

I also processed 210280 for one index and hit a hard C100 on the next one so I'm not doing anything more with it. Status:

210280, i=2321, sz 101, C100

[mataje]

199152: line 5004, size 137, 2^3*3^2, C130 RETIRED

[Greebley]

232956 lost the down driver at 101 digits. It is currently between drivers with a 2^2*5.

232800 is up to 128 digits and has the guide 2^5*7 (currently squared) which has been persistent. It started factoring a C124 over the weekend which will be my largest attempt to date.

[Greebley]

Originally Posted by Greebley

232956 lost the down driver at 101 digits. It is currently between drivers with a 2^2*5.

Well it picked up 2^4 * 31 which means it is unlikely to escape before getting too large for me to handle. Another hopeful bites the dust.

[Mini-Geek]

After a remarkably level run of almost 50 lines with a few different power of 2 guides, 112584 acquired the downdriver at i=556, size 101! Currently hung up on a c93 resisting B1=25e4 ECM.
Has anyone else noticed that 2^2, unaccompanied by any low factors making it a driver or guide, (almost?) always lowers the sequence? It could be called a 'downguide'. (2^2 is listed as a guide just like the others on the Mersenne Wiki)

[henryzz]

Originally Posted by Mini-Geek

After a remarkably level run of almost 50 lines with a few different power of 2 guides, 112584 acquired the downdriver at i=556, size 101!
Has anyone else noticed that 2^2, unaccompanied by any low factors making it a driver or guide, (almost?) always lowers the sequence? It could be called a 'downguide'. (2^2 is listed as a guide just like the others on the Mersenne Wiki)

there are some recent posts about that in the Odds and ends...and class records thread

[KriZp]

Originally Posted by Mini-Geek

Has anyone else noticed that 2^2, unaccompanied by any low factors making it a driver or guide, (almost?) always lowers the sequence? It could be called a 'downguide'. (2^2 is listed as a guide just like the others on the Mersenne Wiki)

yes, I noticed that for my 239778 sequence, which had 2^2 for quite some time before it aquired the downdriver a few hours ago. currently size 101, index 1071 C89 soon to be gnfs'ed

[Mini-Geek]

I lost the downdriver for 112584 at i=655 sz 79. That's 22 digits in 99 lines. Quite a good downdriver run, sorry to see it go. But it didn't change to a driver, just the 2^3 guide, which changed to 2^2 (the 'downguide') a few dozen lines later. At size 80 and climbing slowly now due to a 3 factor that's being somewhat persistent.
Edit: reacquired the downdriver! at i=715, sz 83 I hope this one lasts at least as long as the last!
Edit 2: I just got a neat P+1 factor! That's my first "neat" factor. (by aliqueit.exe default cutoffs, which is ECM/P-1: 45 digits, P+1: 40 digits) It was of a c72 from 112584:726.

Using B1=250000, B2=170973772, polynomial x^1, x0=3527853185
Step 1 took 266ms
Step 2 took 266ms
********** Factor found in step 2: 1710336371667449047176115976918150255117
[Jul 14 2009, 18:55:22] *** Neat 40-digit factor found: 1710336371667449047176115976918150255117

P+1 is 2 * 3 * 13 * 31^2 * 163 * 8231 * 79967 * 84673 * 202729 * 230387 * 53776649. I lost the downdriver, again, (this time at i=735, sz 79, 4 digits in 20 lines) and am in a power of 2 guide, again.

[10metreh]

Originally Posted by Mini-Geek

I lost the downdriver for 112584 at i=655 sz 79. That's 22 digits in 99 lines. Quite a good downdriver run, sorry to see it go. But it didn't change to a driver, just the 2^3 guide, which changed to 2^2 (the 'downguide') a few dozen lines later. At size 80 and climbing slowly now due to a 3 factor that's being somewhat persistent.
Edit: reacquired the downdriver! at i=715, sz 83 I hope this one lasts at least as long as the last!
Edit 2: I just got a neat P+1 factor! That's my first "neat" factor. (by aliqueit.exe default cutoffs, which is ECM/P-1: 45 digits, P+1: 40 digits) It was of a c72 from 112584:726.

Using B1=250000, B2=170973772, polynomial x^1, x0=3527853185
Step 1 took 266ms
Step 2 took 266ms
********** Factor found in step 2: 1710336371667449047176115976918150255117
[Jul 14 2009, 18:55:22] *** Neat 40-digit factor found: 1710336371667449047176115976918150255117

P+1 is 2 * 3 * 13 * 31^2 * 163 * 8231 * 79967 * 84673 * 202729 * 230387 * 53776649. I lost the downdriver, again, (this time at i=735, sz 79, 4 digits in 20 lines) and am in a power of 2 guide, again.

Congratulations on the P+1 factor! That'll be in the all-time top 20, for sure! Shame about the downdriver though.

[Mini-Geek]

Originally Posted by 10metreh

Congratulations on the P+1 factor! That'll be in the all-time top 20, for sure!

Really? Wow! Is there a list that goes that low? The only list I know of for this is Zimmerman's top 10 (#10 is 42 digits, so it certainly wouldn't be a stretch for my 40 digit factor to be within the top 20, just wondering if it's known exactly).
I don't suppose this would count:

Input number is (991#-1)*1577545993667029854782462821709*2049825230786653583738247845011 (473 digits)
Using B1=983, B2=1014, polynomial x^1, x0=3770182560
Step 1 took 16ms
Step 2 took 47ms
********** Factor found in step 2: 19649288510530675457635414441530973968028056560270178760163094612807087579117222328838467049939300222263018614960316970059367632623084520289159762277685706141788095679442344974064203568968298530551124858332193301576974333066317468633561818590965385004001920654119546949528482322103750771653865564789273369859966306024106155051816131935006029725093179578640416314145736960424258769442998811239035580823050358968029
Found probable prime factor of 413 digits:
...
Report your potential champion to Paul Zimmermann <zimmerma@loria.fr>
(see http://www.loria.fr/~zimmerma/records/Pplus1.html)

Originally Posted by 10metreh

Shame about the downdriver though.

Yeah. Right now I've got the 2^2 guide (just lost a 3 factor that was pushing it up, so it's now the downguide ), sz 90. I think this piggy's still got a chance to come home before I drop it.

[10metreh]

Originally Posted by Mini-Geek

I don't suppose this would count:
[code]Input number is (991#-1)*1577545993667029854782462821709*2049825230786653583738247845011 (473 digits)
Using B1=983, B2=1014, polynomial x^1, x0=3770182560
Step 1 took 16ms
Step 2 took 47ms
********** Factor found in step 2: 19649288510530675457635414441530973968028056560270178760163094612807087579117222328838467049939300222263018614960316970059367632623084520289159762277685706141788095679442344974064203568968298530551124858332193301576974333066317468633561818590965385004001920654119546949528482322103750771653865564789273369859966306024106155051816131935006029725093179578640416314145736960424258769442998811239035580823050358968029
Found probable prime factor of 413 digits:

No, that wouldn't count.

OTOH (IIRC), one person once "constructed" an ECM curve with a low B1 (about 15e4) that found a 74-digit prime factor. PaulZ was too suspicious.