mersenneforum.org - Factoring humongous Cunningham numbers

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[QUOTE=LaurV;350429]Did anyone "put a name to unknown"? (no, it is not me, nor anybody I know, I am just curious).[/QUOTE]

???

[QUOTE=BudgieJane;350445]???[/QUOTE]
::yucky::

[QUOTE=xilman;344850]If anyone can put a name to "Unknown", please inform me and I'll amend the table[/QUOTE]

Who is this "unknown" and what are they doing?

wouldn't be simpler to click on the link to Paul's post and see for yourself? (the small blue arrow that follows after the "quote" line in the "quote" tags)

(of course, once arrived there, you have to use the horizontal scroll bar to go as right as possible to see the names of the contributors. edit: maybe the contributor is yourself and you don't know! haha, this would be nice, for once in my life I did not argue in vain)

No, unfortunately it's not me, although I am dabbling in Homogeneous Cunninghams. Sorry to have disturbed the thread.

September update

Another 22 numbers have been completely factored since the last update, principally Jojn Becker, though tom Womack, Rich Smith and Bob Silverman have also had successes. Bob found a p59 which, he reports, is the largest he's ever found by ECM. There are now 409 composites remaining in the [URL="http://www.leyland.vispa.com/numth/factorization/anbn/main.htm"]tables[/URL].

The new results are[code]

10+3 250 C172 11111331168279477350521529239323509371477106675566642622670157501. P108 J Becker SNFS 2013-08-23
11+8 206 C149 7058159932949476800372481755555275872078447668715677341. P94 R Smith SNFS 2013-08-24
7+4 232 C190 5818088034021922653952003113824434561721346162535830746008262924054279753521. P114 J Becker SNFS 2013-08-24
7+4 233 C157 6169788339972357769738760723965227145927286789303874616869243684119650147783. P81 J Becker SNFS 2013-08-24
7-5 233 C165 39618400175673965146722572027261472270699413496931966810294386258827. P98 J Becker SNFS 2013-08-25
8+3 218 C187 2798449227070012486927532094578571060744679336703847037101997580055251101. P114 J Becker SNFS 2013-08-27
7-4 233 C194 3854139334699775603773952484340976403522901401921307677923718905329711903027. P119 J Becker SNFS 2013-08-28
5-3 329 C190 424340253638994605398657009324367894281056084487. P143 J Becker SNFS 2013-08-29
11+3 209 C177 11051037941841760421666373864926424725555887696033. P128 J Becker SNFS 2013-08-29
11+7 209 C172 69463346237633859955293110053518075075875981647549801465421. P113 J Becker SNFS 2013-08-30
11+6 209 C182 1057243012123407594133036252453903436297629874660394228592637105143933960191577463658646223. P92 J Becker SNFS 2013-08-30
11+2 209 C178 15096467592199601611829560145983274600529060470845438097152489299947059309049. P102 J Becker SNFS 2013-08-31
11+7 211 C191 132543402909384600642776053206795745766701084272268880015200363. P129 J Becker SNFS 2013-09-03
8+5 242 C158 519823245824271887522064219809007964551668978330639507221. P102 J Becker SNFS 2013-09-03
8+7 232 C171 25272470754441242864922680601402869591200946212334520884371339175945281252883609473. P89 J Becker SNFS 2013-09-04
11+2 224 C159 1904487641805871068792885563959845073253123282583827936621441. P99 J Becker SNFS 2013-09-05
8-5 263 C160 10520646749671083087012064166113328635630447134768534319970859227191. P93 T Womack SNFS 2013-09-05
9+7 223 C149 65076508497186709891912160004604322782885652684661235165219. P90 R Smith SNFS 2013-09-22
9+8 211 C201 8346272107560016814897329568137739902584099576881156547283599782723417595910511232527914787867. P107 R Smith SNFS 2013-09-25
9+7 251 C227 203982953647185121949308565330130100757030829704474383. P173 R Silverman SNFS 2013-09-25
9+2 257 C227 15288186656060241242010400118735252753781115183282252554073. P169 R Silverman SNFS 2013-09-27
11+8 224 C170 13093479968747490591491312421218465585778564128270740481. P115 J Becker SNFS 2013-09-28
[/code]

Keep 'em coming!

Paul

[QUOTE=xilman;354519]Another 22 numbers have been completely factored since the last update, principally Jojn Becker, though tom Womack, Rich Smith and Bob Silverman have also had successes. Bob found a p59 which, he reports, is the largest he's ever found by ECM. There are now 409 composites remaining in the [URL="http://www.leyland.vispa.com/numth/factorization/anbn/main.htm"]tables[/URL].

The new results are[code]

10+3 250 C172 11111331168279477350521529239323509371477106675566642622670157501. P108 J Becker SNFS 2013-08-23
11+8 206 C149 7058159932949476800372481755555275872078447668715677341. P94 R Smith SNFS 2013-08-24
7+4 232 C190 5818088034021922653952003113824434561721346162535830746008262924054279753521. P114 J Becker SNFS 2013-08-24
7+4 233 C157 6169788339972357769738760723965227145927286789303874616869243684119650147783. P81 J Becker SNFS 2013-08-24
7-5 233 C165 39618400175673965146722572027261472270699413496931966810294386258827. P98 J Becker SNFS 2013-08-25
8+3 218 C187 2798449227070012486927532094578571060744679336703847037101997580055251101. P114 J Becker SNFS 2013-08-27
7-4 233 C194 3854139334699775603773952484340976403522901401921307677923718905329711903027. P119 J Becker SNFS 2013-08-28
5-3 329 C190 424340253638994605398657009324367894281056084487. P143 J Becker SNFS 2013-08-29
11+3 209 C177 11051037941841760421666373864926424725555887696033. P128 J Becker SNFS 2013-08-29
11+7 209 C172 69463346237633859955293110053518075075875981647549801465421. P113 J Becker SNFS 2013-08-30
11+6 209 C182 1057243012123407594133036252453903436297629874660394228592637105143933960191577463658646223. P92 J Becker SNFS 2013-08-30
11+2 209 C178 15096467592199601611829560145983274600529060470845438097152489299947059309049. P102 J Becker SNFS 2013-08-31
11+7 211 C191 132543402909384600642776053206795745766701084272268880015200363. P129 J Becker SNFS 2013-09-03
8+5 242 C158 519823245824271887522064219809007964551668978330639507221. P102 J Becker SNFS 2013-09-03
8+7 232 C171 25272470754441242864922680601402869591200946212334520884371339175945281252883609473. P89 J Becker SNFS 2013-09-04
11+2 224 C159 1904487641805871068792885563959845073253123282583827936621441. P99 J Becker SNFS 2013-09-05
8-5 263 C160 10520646749671083087012064166113328635630447134768534319970859227191. P93 T Womack SNFS 2013-09-05
9+7 223 C149 65076508497186709891912160004604322782885652684661235165219. P90 R Smith SNFS 2013-09-22
9+8 211 C201 8346272107560016814897329568137739902584099576881156547283599782723417595910511232527914787867. P107 R Smith SNFS 2013-09-25
9+7 251 C227 203982953647185121949308565330130100757030829704474383. P173 R Silverman SNFS 2013-09-25
9+2 257 C227 15288186656060241242010400118735252753781115183282252554073. P169 R Silverman SNFS 2013-09-27
11+8 224 C170 13093479968747490591491312421218465585778564128270740481. P115 J Becker SNFS 2013-09-28
[/code]

Keep 'em coming!

Paul[/QUOTE]

The report says "SNFS" for my results..... They were both by ECM.

I am nearly done with a complete ECM pass through the tables. I have
started some SNFS work. I plan to work on 1st holes.

[QUOTE=R.D. Silverman;354528]The report says "SNFS" for my results..... They were both by ECM.

I am nearly done with a complete ECM pass through the tables. I have
started some SNFS work. I plan to work on 1st holes.[/QUOTE]Oops!

That''s what comes from liberal use of cut-and-paste and parsimonious use of editorial judgement.

I'll fix it.

Paul

[QUOTE=xilman;354574]Oops!

That''s what comes from liberal use of cut-and-paste and parsimonious use of editorial judgement.

I'll fix it.

Paul[/QUOTE]

I am nearly done with an ECM pass through all of the tables.
I used first limit 200 x 10^6 throughout, and ran ~800 curves on each
number. There were 550 numbers when I started, so I have run
over 400,000 curves in total.

I found only one factor over 55 digits.

Was I just unlucky? The expected number of curves to find a 55D
factor with B1 = 200M is only about 10,000. It takes about 55,000
curves to find a 60D factor. I didn't find any. It only takes about 335K
curves to find a 65D factor. I didn't find any of those either.

My total effort was about about 1.3p65.

[QUOTE=R.D. Silverman;354642]Was I just unlucky?[/QUOTE]I don't know. I'm sure I read a paper some time back about the statistics of various factoring methods.

I'll see if I can find it and let you know. :wink:

[QUOTE=R.D. Silverman;354642]I am nearly done with an ECM pass through all of the tables.
I used first limit 200 x 10^6 throughout, and ran ~800 curves on each
number. There were 550 numbers when I started, so I have run
over 400,000 curves in total.

I found only one factor over 55 digits.

Was I just unlucky? The expected number of curves to find a 55D
factor with B1 = 200M is only about 10,000. It takes about 55,000
curves to find a 60D factor. I didn't find any. It only takes about 335K
curves to find a 65D factor. I didn't find any of those either.

My total effort was about about 1.3p65.[/QUOTE]

My guess is that yes, you were just unlucky. In the last 3 days I've found (via NFS) two factors under 60 digits, a p56 from 11+8,224 and a p58 from 11+3,224. (I still wouldn't call them ECM misses, since the NFS difficulty was only about 200.) So there apparently are (or were) still some relatively small factors out there.