Factoring humongous Cunningham numbers - Page 168

jyb · 2022-01-10, 05:14

Time for another update! The tables and ECMnet server have been updated to reflect all factors reported to me through the end of January 9 (GMT). There were 29 new factors found since the last update, of which 25 completed the factorization of their respective numbers. There are now 725 composites remaining in the tables.

The range of SNFS difficulties remains as it was (237 to 310). All of the lowest-difficulty numbers are obligatory quartics, with the lowest non-quartic difficulty still at 259. There are a number of octics, the easiest of which has a nominal difficulty of 258. An unreported factor of 5-2,391, presumably found by ECM, has left a 161-digit composite cofactor, currently the minimal digit count in the tables.

Here are the factors found since the last update, showing appropriate credit:

Code:

9-5	271	C233	39104239342844157695429060205817305181852125517975928729.	P177						NFS@Home & R Dickerson	SNFS	2021-09-12
8+3	930M	C188	8140818645611617140423189084010180374627188803000899172278298237756498599357784319269741.	P100		NFS@Home & S Batalov	SNFS	2021-09-16
9+7	271	C229	3885965441968856699370374240308462878959025380180007625297883371.	P165					NFS@Home & S Wellman	SNFS	2021-09-19
7+3	307	C254	18140074580349081773625509944092490584698753692351237.	P202							S Wellman		ECM	2021-09-25
9+2	271	C241	5926157860543723227651875669367803538786282364281975856313272142522523278313091.	P162			NFS@Home & S Wellman	SNFS	2021-10-02
12+5	239	C244	716432890148331005649161159793633954586840151635123086536326312096381.	C175					NFS@Home & S Wellman	SNFS	2021-10-08
12+5	239	C175	145446532901608734743156187774547641718054018904269736397419695451073863.	P104				NFS@Home & S Wellman	SNFS	2021-10-08
8+5	331	C274	100160137036652736218188763001228608424587025950005150135757.	P215						J Becker		ECM	2021-10-09
5+2	434	C216	6140062594424159415238216899833031362609698774882303442588981172316698922120981789402894323505973249.	P116	NFS@Home & G Childers	SNFS	2021-10-11
9-7	271	C245	44187799856451134135336761569870772025101337420212707613982574409412374479175133977213216024294816246453250053.	P135	NFS@Home & S Wellman	SNFS	2021-10-14
9+5	271	C244	3978021982652071925339899641066513797405893280807664162837031398250437568925016611924368966286969.	P148	NFS@Home & S Wellman	SNFS	2021-10-17
5+3	403	C229	451143474473341391302155370206166306457560480754495380669106795937809790399469997.	P148			NFS@Home & G Childers	SNFS	2021-10-21
5-3	403	C239	39034039443180437550708294288604997478851108213078908428987387120967749205379036858017799099853924659.	P138	NFS@Home & G Childers	SNFS	2021-10-28
9+2	542L	C248	181792705400038253097293884216993662632821470249259693.	C195							S Wellman		ECM	2021-10-30
9+8	272	C206	12196362391754908707650574017942397551796128797843500213182427014057548673921.	P130				NFS@Home & G Childers	SNFS	2021-11-02
5+4	434	C238	1271848759982419371615328924328958322427002631628161551468678133404488584820027500584868004008460578310964994163197717.	P120	NFS@Home & G Childers	SNFS	2021-11-08
9+2	542L	C195	317085364010587722125284939344215930343630966580992288080839437845387169810045439854849929.	P106		NFS@Home & G Childers	SNFS	2021-11-14
8-3	341	C193	946119245904820167647403108736595927443363677510932248351367655917.	P127					NFS@Home & G Childers	GNFS	2021-11-15
4+3	1455M	C190	847395492802241556878325362685126182377614572458864812415321.	P130						Yoyo@home		ECM	2021-11-21
9+2	610L	C206	221074308025011194606491003018989473245604278278846736266766720153768223101.	P131				NFS@Home & G Childers	SNFS	2021-11-21
9+8	542L	C254	51070089715414774679413704930304091013352852290301744177.	C198						NFS@Home & S Wellman	SNFS	2021-12-10
9+8	542L	C198	151157653519931983365542919135475698380805343624846454413993808160471907694398384977326962801.	P106		NFS@Home & S Wellman	SNFS	2021-12-10
5+3	434	C239	52122028135442044566018468497279113711192389397645960452428328548021754721975896490704910589594048202101255374611255973.	P121	NFS@Home & E Engler	SNFS	2021-12-13
8+3	786M	C219	10562792921245810171122083156004211885148335826980378632877.	P161						Yoyo@home		ECM	2021-12-23
10+7	295	C227	457341614808199407277408623082448399936231940279243725217432868463853074635799086321.	P144			NFS@Home & G Childers	SNFS	2021-12-23
4-3	431	C225	556859063535835231081161058638604473819789066947505978160177633252472123.	P153				NFS@Home & S Wellman	SNFS	2021-12-23
9+8	610L	C214	1276904990213738009765348776742310899222071691743016987255029225837402287533203826174892309467432081.	P115	NFS@Home & R Smith	SNFS	2022-01-06
5-2	391	C215	124700029456198126467940219170901975383261911784610969.	C161							Unknown			ECM	2022-01-07
3+2	1890L	C191	15865605444487510531731227246783412616457002809098020468761661.	P129						NFS@Home & G Childers	GNFS	2022-01-07

EdH · 2022-01-11, 17:44

Quote:

Originally Posted by jyb

. . .
An unreported factor of 5-2,391, presumably found by ECM, has left a 161-digit composite cofactor, currently the minimal digit count in the tables.
. . .

If it's still not taken, I'll run it in my next window of opportunity.

richs · 2022-01-12, 14:38

Quote:

Originally Posted by EdH

If it's still not taken, I'll run it in my next window of opportunity.

You can reserve here: http://www.chiark.greenend.org.uk/uc...mack/homcun.pl

EdH · 2022-01-12, 14:55

Quote:

Originally Posted by richs

You can reserve here: http://www.chiark.greenend.org.uk/uc...mack/homcun.pl

Thanks. I was waiting until I get a window in my current work, in case someone else may like to grab it. I should have a window tonight, but it might occur after bedtime. If it looks right and no one else has reserved it, I will then.

jyb · 2022-01-18, 17:59

There's another even-lower-hanging piece of fruit available now. Yoyo@home just found a 56-digit factor of 5+2,850L, leaving a 141-digit composite cofactor. Anybody interested in a relatively easy GNFS job can reserve it here.

kruoli · 2022-01-18, 20:56

It should be done early next morning my time.

charybdis · 2022-01-29, 21:09

Now a c169 available from 6-5,349. This may be of interest to those testing CADO parameters in this size range.

EdH · 2022-01-30, 03:21

Quote:

Originally Posted by charybdis

Now a c169 available from 6-5,349. This may be of interest to those testing CADO parameters in this size range.

Is this a hint?

Actually, I'm going to let this sit a bit while some others brew. . .

charybdis · 2022-01-30, 03:30

Quote:

Originally Posted by EdH

Is this a hint?

Actually, I'm going to let this sit a bit while some others brew. . .

You may indeed have been one of the intended readers of this post

I'm also sitting this one out. Focused on the newly extended base-2 Cunninghams for the time being.

VBCurtis · 2022-01-30, 06:08

I'm finishing the 800^ aliqueit powers, then I have a C175 to do- so I won't likely get to this in Feb.
I am collecting timing data on C160+ right now, including finally testing 3LP on a C163.
Anyway, I'll pass on this one too.

charybdis · 2022-02-02, 16:13

And if a c169 is too big, there's now a c151 from 11+6,262 too.

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2022-01-18, 17:59	#1842
jyb Aug 2005 Seattle, WA 2·13·71 Posts	There's another even-lower-hanging piece of fruit available now. Yoyo@home just found a 56-digit factor of 5+2,850L, leaving a 141-digit composite cofactor. Anybody interested in a relatively easy GNFS job can reserve it here.

2022-01-18, 20:56	#1843
kruoli "Oliver" Sep 2017 Porta Westfalica, DE 2450₈ Posts	It should be done early next morning my time.

2022-01-29, 21:09	#1844
charybdis Apr 2020 5²×37 Posts	Now a c169 available from 6-5,349. This may be of interest to those testing CADO parameters in this size range.

2022-01-30, 06:08	#1847
VBCurtis "Curtis" Feb 2005 Riverside, CA 2·5·563 Posts	I'm finishing the 800^ aliqueit powers, then I have a C175 to do- so I won't likely get to this in Feb. I am collecting timing data on C160+ right now, including finally testing 3LP on a C163. Anyway, I'll pass on this one too.

2022-02-02, 16:13	#1848
charybdis Apr 2020 5²·37 Posts	And if a c169 is too big, there's now a c151 from 11+6,262 too.