Contribution and Reservation

(64·10²⁵⁰+53)/9 =: 7(1)₂₄₉7_<251>; = 21391 · [3324347207288631251980324019966860413777341457206821144925955360250157127348469501711519382502506246136744944654813291155678140858824323832972330003791833533313595021790057085274700159464780099626530368431167832785335473381848025389701795666921187_<247>] SUBMIT/RESERVE

Status

Expression:	(64·10²⁵⁰+53)/9
Composite Factor:	332434720728863125198032401996686041377734145720682114492595 536025015712734846950171151938250250624613674494465481329115 567814085882432383297233000379183353331359502179005708527470 015946478009962653036843116783278533547338184802538970179566 6921187 (247-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 252.41-digit and the GNFS difficulty is 246.52-digit. SNFS must be faster than GNFS. It will take about 1080 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 71117_250.
Put the following polynomial file 71117_250.poly in there too.
And then, run "perl factMsieve.pl 71117_250".

71117_250.poly ^*1

n: 3324347207288631251980324019966860413777341457206821144925955360250157127348469501711519382502506246136744944654813291155678140858824323832972330003791833533313595021790057085274700159464780099626530368431167832785335473381848025389701795666921187
m: 400000000000000000000000000000000000000000
deg: 6
c6: 625
c0: 212
skew: 0.84
type: snfs
lss: 1
rlim: 113000000
alim: 113000000
lpbr: 31
lpba: 31
mfbr: 62
mfba: 62
rlambda: 2.8
alambda: 2.8

*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 247-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	1430	Serge Batalov	Aug 8, 2008
		200	Serge Batalov	Nov 30, 2008
		1630 / 0
45	11e6	400	Serge Batalov	Nov 30, 2008
		392	Serge Batalov	Dec 1, 2008
		200	Markus Tervooren	Dec 31, 2008
		992 / 2703
		/ 1711
50	43e6	392	Serge Batalov	Dec 1, 2008
		392 / 7264 (880)
		/ 6872 (488)
55	11e7	0 / 17554 (2851)
55	11e7	/ 17554 (2851)
60	26e7	0 / 41953 (7551)
60	26e7	/ 41953 (7551)

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

echo 3324347207288631251980324019966860413777341457206821144925955360250157127348469501711519382502506246136744944654813291155678140858824323832972330003791833533313595021790057085274700159464780099626530368431167832785335473381848025389701795666921187 | ecm -n -c 1711 11e6

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

echo 3324347207288631251980324019966860413777341457206821144925955360250157127348469501711519382502506246136744944654813291155678140858824323832972330003791833533313595021790057085274700159464780099626530368431167832785335473381848025389701795666921187 | ecm -n -c 6872 43e6

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

echo 3324347207288631251980324019966860413777341457206821144925955360250157127348469501711519382502506246136744944654813291155678140858824323832972330003791833533313595021790057085274700159464780099626530368431167832785335473381848025389701795666921187 | ecm -n -c 17554 11e7

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

echo 3324347207288631251980324019966860413777341457206821144925955360250157127348469501711519382502506246136744944654813291155678140858824323832972330003791833533313595021790057085274700159464780099626530368431167832785335473381848025389701795666921187 | ecm -n -c 41953 26e7

Submit factors

Make reservation

Back to Factorizations of near-repdigit numbers