Contribution and Reservation

(64·10²⁴⁷+53)/9 =: 7(1)₂₄₆7_<248>; = 7 · 11² · 31 · 239 · 56179 · [201706760763723681688414343623659115570000346301131532609207264679026281558386955312032517357328255392460627105731623712812820596340816684369873409379154521627220139814084217518297808150587809495452707435615702607490869675335752844087201_<237>] SUBMIT/RESERVE

Status

Expression:	(64·10²⁴⁷+53)/9
Composite Factor:	201706760763723681688414343623659115570000346301131532609207 264679026281558386955312032517357328255392460627105731623712 812820596340816684369873409379154521627220139814084217518297 808150587809495452707435615702607490869675335752844087201 (237-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.

SNFS

Use GGNFS and/or Msieve if GMP-ECM cannot find a factor. The SNFS difficulty of this composite number is 248.81-digit and the GNFS difficulty is 236.30-digit. SNFS must be faster than GNFS. It will take about 819 CPU-days to factor this composite number on 64-bit Opteron-2600MHz.

Put factMsieve.pl to which $GGNFS_BIN_PATH and $NUM_CPUS were modified properly in the working directory 71117_247.
Put the following polynomial file 71117_247.poly in there too.
And then, run "perl factMsieve.pl 71117_247".

71117_247.poly ^*1

n: 201706760763723681688414343623659115570000346301131532609207264679026281558386955312032517357328255392460627105731623712812820596340816684369873409379154521627220139814084217518297808150587809495452707435615702607490869675335752844087201
m: 200000000000000000000000000000000000000000
deg: 6
c6: 10
c0: 53
skew: 1.32
type: snfs
lss: 1
rlim: 98000000
alim: 98000000
lpbr: 30
lpba: 30
mfbr: 62
mfba: 62
rlambda: 2.7
alambda: 2.7

*1 These parameters were not fully adjusted. The approximate expressions which were used for making the parameters are: deg=expt<=105?4:expt<=210?5:6 or expt<=144?4:6; d=log10(c[deg])+deg*log10(m)[digits]; time=10^(d/30-4)[hours]; skew=|c0/c[deg]|^(1/deg); rlim=round(7*10^(d/60+3)); lpbr=floor(d/25+21); mfbr=floor(d/8+31); rlambda=floor(d/25+18)/10;

Efforts by ECM

The efforts by ECM to find small factors of this 237-digit composite number so far are as follows. According to the reports, unknown prime factors of this composite number are probably 35-digit or more. Please report your efforts by ECM. (Anonymous reports are not acceptable)

Level	B1	Reported runs Total / Required runs (Required runs for lower level)	Name
35	1e6	904	Serge Batalov	Aug 8, 2008
35	1e6	904 / 825
40	3e6	0 / 2089
40	3e6	/ 2089
45	11e6	0 / 4437 (606)
45	11e6	/ 4437 (606)
50	43e6	0 / 7548 (1265)
50	43e6	/ 7548 (1265)
55	11e7	0 / 17769 (3131)
55	11e7	/ 17769 (3131)

Command line to find prime factors up to about 40-digit

echo 201706760763723681688414343623659115570000346301131532609207264679026281558386955312032517357328255392460627105731623712812820596340816684369873409379154521627220139814084217518297808150587809495452707435615702607490869675335752844087201 | ecm -n -c 2089 3e6

Command line to find prime factors up to about 45-digit

echo 201706760763723681688414343623659115570000346301131532609207264679026281558386955312032517357328255392460627105731623712812820596340816684369873409379154521627220139814084217518297808150587809495452707435615702607490869675335752844087201 | ecm -n -c 4437 11e6

Command line to find prime factors up to about 50-digit

echo 201706760763723681688414343623659115570000346301131532609207264679026281558386955312032517357328255392460627105731623712812820596340816684369873409379154521627220139814084217518297808150587809495452707435615702607490869675335752844087201 | ecm -n -c 7548 43e6

Command line to find prime factors up to about 55-digit

echo 201706760763723681688414343623659115570000346301131532609207264679026281558386955312032517357328255392460627105731623712812820596340816684369873409379154521627220139814084217518297808150587809495452707435615702607490869675335752844087201 | ecm -n -c 17769 11e7

Submit factors

Make reservation

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