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Contribution and Reservation


2·10197-9 =
1(9)1961<198>
= 11 · 24422549 · 3069053877636163811209<22> · 17082856976752619130670684090199212230671<41> · [14199769786361877131481352798360193879811392041671569479063650284980510802646880763045758186153993852586423863728125991994323271<128>] (Dmitry Domanov / ECMNET, GMP-ECM B1=11000000, sigma=239735945 for P41 / Jan 14, 2010) SUBMIT/RESERVE

Status

Expression:2·10197-9
Composite Factor:141997697863618771314813527983601938798113920416715694790636
502849805108026468807630457581861539938525864238637281259919
94323271
(128-digit)
Status:Not factored. Not reserved. You can submit its factors or reserve it for submitting in the future.

How to factor it

ECM, P-1, P+1

Look for prime factors by GMP-ECM first. Refer to the section "Efforts by ECM". Not only ECM but also P-1/P+1 may be helpful.

NFS

Use GGNFS and/or Msieve if GMP-ECM cannot find a factor. The SNFS difficulty of this composite number is 197.30-digit and the GNFS difficulty is 127.15-digit. GNFS must be faster than SNFS. It will take about 5 CPU-days to factor this composite number on 64-bit Opteron-2600MHz.

Steps of GNFS

  1. Put factMsieve.pl to which $GGNFS_BIN_PATH and $NUM_CPUS were modified properly in the working directory 19991_197.
  2. Put the following composite number file 19991_197.n in there too.
  3. And then, run "perl factMsieve.pl 19991_197".
19991_197.n
n: 14199769786361877131481352798360193879811392041671569479063650284980510802646880763045758186153993852586423863728125991994323271

See also


Efforts by ECM

The efforts by ECM to find small factors of this 128-digit composite number so far are as follows. According to the reports, unknown prime factors of this composite number are probably 40-digit or more. Please report your efforts by ECM. (Anonymous reports are not acceptable)

LevelB1Reported runs
Total / Required runs
(Required runs for lower level)		Name 
403e611Dmitry DomanovJan 13, 2010
11 / 0  
4511e6950Dmitry DomanovJan 14, 2010
950 / 4478  
/ 3528
5043e60 / 7340 (1006)  
/ 7340 (1006)  
5511e70 / 17710 (3045)  
/ 17710 (3045)  
6026e70 / 42002 (7618)  
/ 42002 (7618)  
Command line to find prime factors up to about 45-digit
echo 14199769786361877131481352798360193879811392041671569479063650284980510802646880763045758186153993852586423863728125991994323271 | ecm -n -c 3528 11e6
Command line to find prime factors up to about 50-digit
echo 14199769786361877131481352798360193879811392041671569479063650284980510802646880763045758186153993852586423863728125991994323271 | ecm -n -c 7340 43e6
Command line to find prime factors up to about 55-digit
echo 14199769786361877131481352798360193879811392041671569479063650284980510802646880763045758186153993852586423863728125991994323271 | ecm -n -c 17710 11e7
Command line to find prime factors up to about 60-digit
echo 14199769786361877131481352798360193879811392041671569479063650284980510802646880763045758186153993852586423863728125991994323271 | ecm -n -c 42002 26e7

Submit polynomial for GNFS

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