Contribution and Reservation

(53·10¹⁹³-17)/9 =: 5(8)₁₉₂7_<194>; = 3³ · 7018213 · 17851313 · 679746483103291781_<18> · 20572446508725500234225553940201_<32> · [1244915789843555096011732458304270596627375015872090006518666492540398283834017403659916118975910672983647063299114503997601252229_<130>] (Serge Batalov / GMP-ECM 6.2.2 B1=3000000, sigma=376038659 for P32 / Apr 23, 2009) SUBMIT/RESERVE

Status

Expression:	(53·10¹⁹³-17)/9
Composite Factor:	124491578984355509601173245830427059662737501587209000651866 649254039828383401740365991611897591067298364706329911450399 7601252229 (130-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.

GNFS

Use GGNFS and/or Msieve if GMP-ECM cannot find a factor. The SNFS difficulty of this composite number is 196.12-digit and the GNFS difficulty is 129.10-digit. GNFS must be faster than SNFS. It will take about 6 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 58887_193.
Put the following polynomial file 58887_193.poly in there too.
And then, run "perl factMsieve.pl 58887_193".

58887_193.poly ^*1

# Murphy_E = 8.039102e-11, selected by Jeff Gilchrist
n: 1244915789843555096011732458304270596627375015872090006518666492540398283834017403659916118975910672983647063299114503997601252229
Y0: -7625018864902528057062799
Y1: 206020157428153
c0: -236039994252092803694771056273920
c1: 2295680456613708995608082784
c2: 6382569547002010190908
c3: -41949142744907584
c4: -48437028643
c5: 48300
skew: 427417.58
type: gnfs
# selected mechanically
rlim: 9300000
alim: 9300000
lpbr: 28
lpba: 28
mfbr: 53
mfba: 53
rlambda: 2.5
alambda: 2.5

*1 These parameters were not fully adjusted. The approximate expressions which were used for making the parameters are: d=log10(n); time=10^(d/21-4)[hours]; rlim=round(3*10^(d/37+3)); lpbr=floor(d/18+21); mfbr=floor(d/5+28); rlambda=floor(d/26+21)/10;

Efforts by ECM

The efforts by ECM to find small factors of this 130-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	118	Makoto Kamada	Apr 22, 2009
35	1e6	118 / 0
40	3e6	500	Erik Branger	May 12, 2009
		500 / 2318
		/ 1818
45	11e6	0 / 4365 (527)
45	11e6	/ 4365 (527)
50	43e6	0 / 7534 (1244)
50	43e6	/ 7534 (1244)
55	11e7	0 / 17765 (3125)
55	11e7	/ 17765 (3125)

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

echo 1244915789843555096011732458304270596627375015872090006518666492540398283834017403659916118975910672983647063299114503997601252229 | ecm -n -c 1818 3e6

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

echo 1244915789843555096011732458304270596627375015872090006518666492540398283834017403659916118975910672983647063299114503997601252229 | ecm -n -c 4365 11e6

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

echo 1244915789843555096011732458304270596627375015872090006518666492540398283834017403659916118975910672983647063299114503997601252229 | ecm -n -c 7534 43e6

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

echo 1244915789843555096011732458304270596627375015872090006518666492540398283834017403659916118975910672983647063299114503997601252229 | ecm -n -c 17765 11e7

Contribution and Reservation

Status

How to factor it

ECM, P-1, P+1

GNFS

See also

Efforts by ECM

Submit polynomial for GNFS

Submit factors

Make reservation