Contribution and Reservation

(16·10²⁴⁶-7)/9 =: 1(7)₂₄₆_<247>; = 2213 · [803333835416980468946126424662348747301300396646081237134106542149922177034693980017070844002610834965105186524074910880152633428729226289099764020685846261987247075362755435055480243008485213636591856203243460360496058643369985439574233067229_<243>] SUBMIT/RESERVE

Status

Expression:	(16·10²⁴⁶-7)/9
Composite Factor:	803333835416980468946126424662348747301300396646081237134106 542149922177034693980017070844002610834965105186524074910880 152633428729226289099764020685846261987247075362755435055480 243008485213636591856203243460360496058643369985439574233067 229 (243-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 247.20-digit and the GNFS difficulty is 242.90-digit. SNFS must be faster than GNFS. It will take about 724 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 17777_246.
Put the following polynomial file 17777_246.poly in there too.
And then, run "perl factMsieve.pl 17777_246".

17777_246.poly ^*1

n: 803333835416980468946126424662348747301300396646081237134106542149922177034693980017070844002610834965105186524074910880152633428729226289099764020685846261987247075362755435055480243008485213636591856203243460360496058643369985439574233067229
m: 100000000000000000000000000000000000000000
deg: 6
c6: 16
c0: -7
skew: 0.87
type: snfs
lss: 1
rlim: 92000000
alim: 92000000
lpbr: 30
lpba: 30
mfbr: 61
mfba: 61
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 243-digit composite number so far are as follows. According to the reports, unknown prime factors of this composite number are probably 45-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
45	11e6	4500	Dmitry Domanov	Sep 2, 2009
45	11e6	4500 / 3835
50	43e6	0 / 6436
50	43e6	/ 6436
55	11e7	0 / 17466 (2670)
55	11e7	/ 17466 (2670)
60	26e7	0 / 41942 (7513)
60	26e7	/ 41942 (7513)
65	85e7	0 / 69396 (13587)
65	85e7	/ 69396 (13587)

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

echo 803333835416980468946126424662348747301300396646081237134106542149922177034693980017070844002610834965105186524074910880152633428729226289099764020685846261987247075362755435055480243008485213636591856203243460360496058643369985439574233067229 | ecm -n -c 6436 43e6

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

echo 803333835416980468946126424662348747301300396646081237134106542149922177034693980017070844002610834965105186524074910880152633428729226289099764020685846261987247075362755435055480243008485213636591856203243460360496058643369985439574233067229 | ecm -n -c 17466 11e7

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

echo 803333835416980468946126424662348747301300396646081237134106542149922177034693980017070844002610834965105186524074910880152633428729226289099764020685846261987247075362755435055480243008485213636591856203243460360496058643369985439574233067229 | ecm -n -c 41942 26e7

Command line to find prime factors up to about 65-digit

echo 803333835416980468946126424662348747301300396646081237134106542149922177034693980017070844002610834965105186524074910880152633428729226289099764020685846261987247075362755435055480243008485213636591856203243460360496058643369985439574233067229 | ecm -n -c 69396 85e7

Submit factors

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