Contribution and Reservation

(44·10¹⁹⁶+1)/9 =: 4(8)₁₉₅9_<197>; = 8933 · 16963 · 25118459058799261_<17> · 22817914192505289037_<20> · 11828090705908675308664466509_<29> · [47591192682295255556939533626276864986616791664971258683837897117422151274096194328168951720826806922476074246980788223343307_<125>] RESERVED

Status

Expression:	(44·10¹⁹⁶+1)/9
Composite Factor:	475911926822952555569395336262768649866167916649712586838378 971174221512740961943281689517208268069224760742469807882233 43307 (125-digit)
Status:	Not factored. Reserved by juno1369 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 198.25-digit and the GNFS difficulty is 124.68-digit. GNFS must be faster than SNFS. It will take about 4 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 48889_196.
Put the following polynomial file 48889_196.poly in there too.
And then, run "perl factMsieve.pl 48889_196".

48889_196.poly ^*1

# Murphy_E = 1.616328e-10, selected by Jeff Gilchrist
n: 47591192682295255556939533626276864986616791664971258683837897117422151274096194328168951720826806922476074246980788223343307
Y0: -1199076728101819988849653
Y1: 46607669934463
c0: 11407148688942894436221615050448
c1: 540253315006657005906842214
c2: 2142543692160211328813
c3: -7110190630780646
c4: -10817133040
c5: 19200
skew: 382315.01
type: gnfs
# selected mechanically
rlim: 7000000
alim: 7000000
lpbr: 27
lpba: 27
mfbr: 52
mfba: 52
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 125-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	500	Erik Branger	Mar 7, 2009
		1818	Wataru Sakai	Aug 19, 2009
		2318 / 2318
45	11e6	0 / 3963
45	11e6	/ 3963
50	43e6	0 / 7465 (1130)
50	43e6	/ 7465 (1130)
55	11e7	0 / 17751 (3097)
55	11e7	/ 17751 (3097)
60	26e7	0 / 42014 (7636)
60	26e7	/ 42014 (7636)

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

echo 47591192682295255556939533626276864986616791664971258683837897117422151274096194328168951720826806922476074246980788223343307 | ecm -n -c 3963 11e6

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

echo 47591192682295255556939533626276864986616791664971258683837897117422151274096194328168951720826806922476074246980788223343307 | ecm -n -c 7465 43e6

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

echo 47591192682295255556939533626276864986616791664971258683837897117422151274096194328168951720826806922476074246980788223343307 | ecm -n -c 17751 11e7

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

echo 47591192682295255556939533626276864986616791664971258683837897117422151274096194328168951720826806922476074246980788223343307 | ecm -n -c 42014 26e7

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

Cancel reservation