Contribution and Reservation

(82·10¹⁹⁶+71)/9 =: 9(1)₁₉₅9_<197>; = 3 · 7 · 19² · 121447 · [98959628220445730595216821633383494653439316782881239608678617617163293768756242988074494799485263617822884068705148575220371298352215760256252230602064405517581300722753829060794649582317_<188>] SUBMIT/RESERVE

Status

Expression:	(82·10¹⁹⁶+71)/9
Composite Factor:	989596282204457305952168216333834946534393167828812396086786 176171632937687562429880744947994852636178228840687051485752 203712983522157602562522306020644055175813007227538290607946 49582317 (188-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 198.82-digit and the GNFS difficulty is 188.00-digit. SNFS must be faster than GNFS. It will take about 18 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 91119_196.
Put the following polynomial file 91119_196.poly in there too.
And then, run "perl factMsieve.pl 91119_196".

91119_196.poly ^*1

n: 98959628220445730595216821633383494653439316782881239608678617617163293768756242988074494799485263617822884068705148575220371298352215760256252230602064405517581300722753829060794649582317
m: 2000000000000000000000000000000000000000
deg: 5
c5: 205
c0: 568
skew: 1.23
type: snfs
lss: 1
rlim: 14400000
alim: 14400000
lpbr: 28
lpba: 28
mfbr: 55
mfba: 55
rlambda: 2.5
alambda: 2.5

*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 188-digit composite number so far are as follows. According to the reports, unknown prime factors of this composite number are probably 20-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
20	11e3	74	Max Dettweiler	Mar 6, 2009
20	11e3	74 / 74
25	5e4	0 / 204
25	5e4	/ 204
30	25e4	0 / 430 (48)
30	25e4	/ 430 (48)
35	1e6	0 / 904 (118)
35	1e6	/ 904 (118)
40	3e6	0 / 2350 (322)
40	3e6	/ 2350 (322)

Command line to find prime factors up to about 25-digit

echo 98959628220445730595216821633383494653439316782881239608678617617163293768756242988074494799485263617822884068705148575220371298352215760256252230602064405517581300722753829060794649582317 | ecm -n -c 204 5e4

Command line to find prime factors up to about 30-digit

echo 98959628220445730595216821633383494653439316782881239608678617617163293768756242988074494799485263617822884068705148575220371298352215760256252230602064405517581300722753829060794649582317 | ecm -n -c 430 25e4

Command line to find prime factors up to about 35-digit

echo 98959628220445730595216821633383494653439316782881239608678617617163293768756242988074494799485263617822884068705148575220371298352215760256252230602064405517581300722753829060794649582317 | ecm -n -c 904 1e6

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

echo 98959628220445730595216821633383494653439316782881239608678617617163293768756242988074494799485263617822884068705148575220371298352215760256252230602064405517581300722753829060794649582317 | ecm -n -c 2350 3e6

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