HCN Table Updates
 

The tables and ECMnet server have once again been updated to reflect all factors reported to me through the end of November 27 (GMT). There were 76 new factors found, 74 of which completed the factorization of their respective numbers.

There are 1125 composites remaining in the tables. The minimum digit counts and SNFS difficulties are rapidly rising. The minimum digit count is now 148. There are 5 composites with size 14x digits, one more with 156 digits, after which all composites have at least 172 digits. There is one composite (already reserved) with SNFS difficulty 207, after which all composites have a difficulty of at least 221.

Here are the factors found since the last update:
[code]
11-5 291 C200 1382692059052256387858158993319709629363715785078428304443505109860053154824264309912657. P113 E Hall SNFS 2019-10-27
8+5 327 C145 1649136106397482014196537692499704656940543411449448601. P90 S Wellman SNFS 2019-10-27
8-3 305 C161 1153407512891920236561908767332054566309734668610291225657798691308725241410341. P83 NFS@Home & C Pinho GNFS 2019-10-27
9+2 308 C184 2908029021569231824162192699493215361636565588021521. P132 Yoyo@home ECM 2019-10-27
11-4 291 C200 489937626892945062047433148428794633918157287149057355987410847811711355337851974678795884725008751. P102 E Hall SNFS 2019-10-27
11+4 260 C162 724552010545440782111220313504025932368218572414958513620192970413201. P93 NFS@Home & C Pinho GNFS 2019-10-28
10+3 260 C150 46909126919960452621363312601724972343972466152059434715587521. P88 NFS@Home & C Pinho GNFS 2019-10-28
7+2 335 C150 1798715041794622593148371692340579024649307462361177017051. P93 NFS@Home & C Pinho GNFS 2019-10-28
9+7 312 C177 825387863386242337286017700167663815402428741433121. P126 E Hall SNFS 2019-10-29
9+8 312 C164 11280001956044551991566074145077330212341395549039973232232001. P103 E Hall SNFS 2019-10-29
8+7 295 C163 40740276067737660362247950737429912678385262899236905903075769215206621. P92 NFS@Home & C Pinho GNFS 2019-10-29
11+9 259 C143 51719034919701328043036063864641016622200478321141547159501474357. P79 S Wellman GNFS 2019-10-29
9+7 318 C166 18644619511216028267449356799401107291199936782468335021198021. P105 E Hall SNFS 2019-10-30
7+4 308 C150 104345920728896980645205896103269006447842204925818153664406529875923770641. P76 NFS@Home & C Pinho GNFS 2019-10-30
9-5 565M C163 1744161177911355785159296094399429738304652346213891076480101. P103 NFS@Home & C Pinho GNFS 2019-10-30
7+3 326 C143 2645279050313211353419009104253224078625299760277426205981395981. P79 S Wellman GNFS 2019-10-30
9-5 575M C163 7128929604330108895894145876290130032870171855989397957909122451. P99 NFS@Home & D Domanov GNFS 2019-10-31
9+5 265 C192 7937334471939547711778423854987620543160372659139721. C140 E Hall SNFS 2019-11-01
9+5 265 C140 58133621956368145018625859367501748390916376201194240371307001. P79 E Hall SNFS 2019-11-01
12-7 235 C187 106884954106283381375447729226148345704677850137678942620067173180590851909948333815501. P101 E Hall SNFS 2019-11-02
3-2 565 C145 53858845380048252603346381128953974416957585213153845094396391991. P80 S Wellman GNFS 2019-11-02
11+9 605L C230 8742421366528304928979493974913829996816463174061. P181 J Becker ECM 2019-11-03
7+3 337 C166 1707236710701046752605175700430461959702924335001031993088611910131266407. P94 NFS@Home & R Dickerson GNFS 2019-11-03
12+11 235 C190 218715405374622523714685060431710630455581780500039424442671653885701107711. P116 E Hall SNFS 2019-11-03
12+5 235 C192 157562801845077769274585270315847296384095845453990564031753114127711128426736691001. P109 E Hall SNFS 2019-11-04
8+3 762L C168 159520726214196947942671514014693512983817801005699814446340223822629103048333. P91 NFS@Home & J Becker GNFS 2019-11-05
11-7 245 C167 62418368646316506175513587658294033166256723505892766720157130858050448958037991. P88 E Hall SNFS 2019-11-05
11+5 242 C212 3776400822883050821804290068450451524708615344664215832088306476079727973169648050329. P127 NFS@Home & J Becker SNFS 2019-11-05
11+6 260 C160 276017567594207723980399962521220184735159530554521. P109 NFS@Home & C Pinho GNFS 2019-11-06
11-8 245 C171 44250987636895425857836598640616497719494342134676501395016365726181. P104 E Hall SNFS 2019-11-06
5+4 425 C168 165952240558687686017704893971249267264234726886437182029579901. P106 NFS@Home & R Dickerson GNFS 2019-11-07
8-7 295 C160 20590739586814317749546391855638550279870455368181837791860872034767906407690471. P81 NFS@Home & C Pinho GNFS 2019-11-07
7-5 323 C147 21241090774719944222686227339971140817080229241836304841328128963361. P79 S Wellman GNFS 2019-11-07
9-8 293 C146 180135932368485180452003308352453312586086170347375686640257933399. P81 S Wellman GNFS 2019-11-07
12+7 238 C146 4989313617613617774958646837842530692894355241143866257. P91 S Wellman GNFS 2019-11-07
6+5 396 C179 12041604226490505404834860497719190640292626088314387324054387208708702978152262953. P97 E Hall SNFS 2019-11-08
11+7 242 C193 12162794501913992585581638449547391118373840760988633. P141 NFS@Home & D Domanov SNFS 2019-11-08
5-2 365 C202 259733462298979241604417133228900645909065108521. P154 E Hall SNFS 2019-11-08
10-7 303 C171 2029834793359781144426190858967628507893843333690840889446543. P111 E Hall SNFS 2019-11-08
5-2 385 C144 1326921668177799098245844061948207565997477237912781247672427580881. P78 S Wellman GNFS 2019-11-08
3+2 636 C181 102799383590941637644154349985426239795053196241. P134 R Silverman SNFS 2019-11-09
11-10 283 C295 3840137801736064879926457546578247454243410424207. C247 J Becker ECM 2019-11-10
9-5 535M C182 3981518625751198077603235065772048118316566245197680512999197752491. P116 E Hall SNFS 2019-11-10
5+2 362 C147 235833768530666747147733728518252924734977802781829447740312406369. P82 S Wellman GNFS 2019-11-12
9-5 535L C183 42910559209837540001325065788249457034535824019238072494223171711. P118 E Hall SNFS 2019-11-13
12+5 975L C170 315835356770149291285817817622011119230852944968186203934978202145760004071275801. P89 NFS@Home & R Dickerson GNFS 2019-11-13
11+9 242 C166 2869188233278547191571403101662304853653761992337019613094027122961. P99 NFS@Home & R Smith SNFS 2019-11-14
12+5 705M C195 72903077382671962888469255333023309944640415569308811. P142 E Hall SNFS 2019-11-15
5+2 438 C182 18844950447654324758941719583763162090175013420048958310514346125501. P115 E Hall SNFS 2019-11-15
7+2 313 C175 209385017986789944059576072133960044594117543180131748159. P119 NFS@Home & J Becker GNFS 2019-11-16
11-8 275 C171 1806264424963007416034322067165548733797106224385526269166040641762121289201. P96 NFS@Home & R Dickerson GNFS 2019-11-16
6+5 393 C177 277075447320436327479302596211725697063732372338322663927599. P118 E Hall SNFS 2019-11-16
9+5 321 C175 253319724584873541647146266422749664893208642256304613723503370647192571863. P101 E Hall SNFS 2019-11-16
9-8 321 C171 71317232546993301097979435265282532979921446609816164042538316071. P106 E Hall SNFS 2019-11-17
9+8 308 C217 288788941511734568189594476696086176259309455303988376729456829866572623991088278769. P133 NFS@Home & J Becker SNFS 2019-11-17
9+5 266 C184 47594629523141577095400836503003950017157565447033254223423523197801. P116 E Hall SNFS 2019-11-18
9+7 308 C230 202207085110504215215700246381346573435176056158971668676402875174020823528551384811331099101995863814739079010961. P116 NFS@Home & J Becker SNFS 2019-11-18
8-7 335 C147 294906921381386091598367532022717538110430283005352821. P93 S Wellman GNFS 2019-11-19
7+5 301 C175 6644103285563382428189119459912378423556521464073599356070485127416928997511. P99 E Hall SNFS 2019-11-19
9+2 526L C211 32181044294698786738562963438869812244664565862292717065715034600349222912598038482123601. P122 NFS@Home & J Becker SNFS 2019-11-19
7-4 301 C213 61574126193315493994164316254825423172613153830693299504688813238379324961. P139 E Hall SNFS 2019-11-20
4-3 473 C171 261525703711941231461201895096488473797365729768602979. P118 NFS@Home & J Becker GNFS 2019-11-20
7-3 301 C213 38861741496858567406985098842444009917602724799883314418900053015916972124466094875018975723665595361. P113 E Hall SNFS 2019-11-21
5+3 1395M C171 5003118473638968094511276427220429797381787960012927083215044953478459709093126191. P89 NFS@Home & J Becker GNFS 2019-11-21
7+6 301 C214 5089151965445201681682052086935773857415647527693111795545373. P153 E Hall SNFS 2019-11-21
11+8 290 C171 13062588932317156565314686995353942994435946206106821864501. P113 NFS@Home & J Becker GNFS 2019-11-21
5+3 364 C167 3742851587745509894356898752969279522344319918256705737. P112 E Hall SNFS 2019-11-22
5+2 364 C202 2100660301006859016411108087334433150891016061109111165055727441. P138 E Hall SNFS 2019-11-22
4-3 427 C184 29075349356218645034704742151717987616862975604723668773977064879744190194985438221. P102 E Hall SNFS 2019-11-23
9+2 526M C242 162447670932509981731014103393292550541925175516880141939905524740513992143733109. P161 NFS@Home & J Becker SNFS 2019-11-23
10-9 303 C182 6332729301902149415693043474779922169743567646313638521817885477. P118 R Silverman SNFS 2019-11-23
7-5 305 C147 6703987770277418414602929117994092194751746964811755394100621. P86 S Wellman GNFS 2019-11-23
4-3 493 C172 14007216162709793466388223638436785588453431715307526611759975705953717. P101 NFS@Home & J Becker GNFS 2019-11-24
3+2 616 C192 2080384215786842681131970057370242911265933770178619841444807155986563523543667649. P111 NFS@Home & S Wellman SNFS 2019-11-24
4+3 490 C147 72820979732757943267678357525549135158226258498967245821169513456932721. P77 S Wellman GNFS 2019-11-26
10-7 259 C205 8975847434266925162883875322401718453000541269535770842209. P147 J Becker SNFS 2019-11-27
[/code]

5-2,395 (SNFS)

[code]
5199528112862840093224982118521566426328549782273997364047852738997703970771980034019889175304709241
2983278540815553634060015673829789148339625983809936338869270133325348318722317269601
[/code]

Error
 

Something has gone wrong in my factorization of 9,2,321-. I have built matrices
twice and each time the LA code has not found any solutions. I have, of course,
eliminated duplicates. I need to investigate.... This may take a while.

[QUOTE=R.D. Silverman;532442]Something has gone wrong in my factorization of 9,2,321-. I have built matrices
twice and each time the LA code has not found any solutions. I have, of course,
eliminated duplicates. I need to investigate.... This may take a while.[/QUOTE]
If you're using msieve >r1024 with mpi support, there is an issue with the square root phase. You can see a little more about it [URL="https://www.mersenneforum.org/showthread.php?p=529622#post529622"]here[/URL].

Edit: It actually might be the LA not supplying the correct data to the SR phase.

[QUOTE=EdH;532450]If you're using msieve >r1024 with mpi support, there is an issue with the square root phase. You can see a little more about it [URL="https://www.mersenneforum.org/showthread.php?p=529622#post529622"]here[/URL].

Edit: It actually might be the LA not supplying the correct data to the SR phase.[/QUOTE]

I use my own code except for the filtering and square root phases. For those, I
use the CWI code. I have my own filter and square root code, but they are very very
slow and inefficient. My siever emits relations in the CWI format.

BTW, msieve outperforms the CWI code except for the square root phase. For that,
Peter's algorithm using fractional ideals with LLL is far better than the msieve
method.

My LA code is very slightly faster than the CWI version. Note that both are very
old, and are single threaded only. They both pre-date multi-core processors.

Why don't I make my code multi-threaded, I hear you ask......

It's simple. I don't have the hardware to perform factorizations that yield matrices
large enough to require multi-threading. My current matrices have about 3M
rows. They take ~20 hours.

I also prefer to use my own code whenever possible. That way, when I want to
tinker/experiment with the internals, I can. I also prefer not to use other people's
'black box' code whenever possible.
.

10-9,259 (SNFS)
[code]
3797813358296835360733351988965624706648429626277082341860009
450000706516588740978380408306628441315663960692724038091819653661646705920256707903609240845196098548160485365977411408368753962944104037723126784641
[/code]

[QUOTE=R.D. Silverman;532456]My current matrices have about 3M
rows. They take ~20 hours.[/QUOTE]
This may be a silly question, but is that a big enough matrix? The reason I ask is, in looking at posts about factorizations of numbers roughly this size, the matrices generally seem to be somewhat larger.

The only diagnostic suggestion I can think of is, run your code on a factorization you did successfuly before, and see if it still works.

[QUOTE=Dr Sardonicus;532622]This may be a silly question, but is that a big enough matrix? The reason I ask is, in looking at posts about factorizations of numbers roughly this size, the matrices generally seem to be somewhat larger.

The only diagnostic suggestion I can think of is, run your code on a factorization you did successfuly before, and see if it still works.[/QUOTE]

Yes, it is plenty big for a C207. I already know that the code works.

9,7,321-
 

[QUOTE=R.D. Silverman;532635]Yes, it is plenty big for a C207. I already know that the code works.[/QUOTE]

To wit:

9,2,321- C191 = p93.p99

Prime factor 1 has 93 digits:
322721219408294237412665101981310579297664782071190968586123188734068728693989321403184012977
Prime factor 2 has 99 digits:
190251761714824161679841565836079598992067967361793666766078692833088238956163543212843148546236303

Final matrix was 2.77M columns.

[QUOTE=Dr Sardonicus;532622]This may be a silly question, but is that a big enough matrix? The reason I ask is, in looking at posts about factorizations of numbers roughly this size, the matrices generally seem to be somewhat larger.
[/QUOTE]

I don't know for sure, but it could be a difference between CWI filtering and msieve or CADO filtering, which is likely what other matrices posted around here use. CWI is not a commonly-used tool around here anymore.

[QUOTE=bsquared;532668]I don't know for sure, but it could be a difference between CWI filtering and msieve or CADO filtering, which is likely what other matrices posted around here use. CWI is not a commonly-used tool around here anymore.[/QUOTE]

My factor base limits were 16M and the LP bound was 325M.

I could use my own filter code, but it was written in 1992 and is horribly inefficient.
It uses sparse Gaussian elimination.