Contribution and Reservation

(47·10²⁰³+43)/9 =: 5(2)₂₀₂7_<204>; = 5113 · [102136167068692005128539452810917704326661885824803876828128735032705304561357759089032314144772584045026837907729752048156116217919464545711367538083751656996327444205402351304952517547862746376339179_<201>] SUBMIT/RESERVE

Status

Expression:	(47·10²⁰³+43)/9
Composite Factor:	102136167068692005128539452810917704326661885824803876828128 735032705304561357759089032314144772584045026837907729752048 156116217919464545711367538083751656996327444205402351304952 517547862746376339179 (201-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 206.07-digit and the GNFS difficulty is 200.01-digit. SNFS must be faster than GNFS. It will take about 31 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 52227_203.
Put the following polynomial file 52227_203.poly in there too.
And then, run "perl factMsieve.pl 52227_203".

52227_203.poly ^*1

n: 102136167068692005128539452810917704326661885824803876828128735032705304561357759089032314144772584045026837907729752048156116217919464545711367538083751656996327444205402351304952517547862746376339179
m: 50000000000000000000000000000000000000000
deg: 5
c5: 376
c0: 1075
skew: 1.23
type: snfs
lss: 1
rlim: 19000000
alim: 19000000
lpbr: 29
lpba: 29
mfbr: 56
mfba: 56
rlambda: 2.6
alambda: 2.6

*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 201-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)

Level	B1	Reported runs Total / Required runs (Required runs for lower level)	Name
40	3e6	2500	Dmitry Domanov	Jul 3, 2009
40	3e6	2500 / 1991
45	11e6	0 / 3867
45	11e6	/ 3867
50	43e6	0 / 7451 (1103)
50	43e6	/ 7451 (1103)
55	11e7	0 / 17748 (3091)
55	11e7	/ 17748 (3091)
60	26e7	0 / 42014 (7634)
60	26e7	/ 42014 (7634)

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

echo 102136167068692005128539452810917704326661885824803876828128735032705304561357759089032314144772584045026837907729752048156116217919464545711367538083751656996327444205402351304952517547862746376339179 | ecm -n -c 3867 11e6

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

echo 102136167068692005128539452810917704326661885824803876828128735032705304561357759089032314144772584045026837907729752048156116217919464545711367538083751656996327444205402351304952517547862746376339179 | ecm -n -c 7451 43e6

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

echo 102136167068692005128539452810917704326661885824803876828128735032705304561357759089032314144772584045026837907729752048156116217919464545711367538083751656996327444205402351304952517547862746376339179 | ecm -n -c 17748 11e7

Command line to find prime factors up to about 60-digit

echo 102136167068692005128539452810917704326661885824803876828128735032705304561357759089032314144772584045026837907729752048156116217919464545711367538083751656996327444205402351304952517547862746376339179 | ecm -n -c 42014 26e7

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