M7508981 has at least 12 prime factors(new factor # record)

[pdazzl]

Originally Posted by kracker

I'm starting as well, doing B1=900000 if that's not taken.
How many curves?

However many curves you can spare or is reasonable for that range

[kracker]

Originally Posted by pdazzl

However many curves you can spare or is reasonable for that range

I don't know... I currently have 4 cores on it.(can throw more in the fray)

Each curve is 6.2GHz/days. Do you think it would be better if I stepped back on the bounds?

[kracker]

Originally Posted by Batalov

1583285088503372039 = 60071849 · 26356523311 ?

Hmm... I thought Primenet didn't directly* accept composite factors?

[ATH]

I checked M566448359 to 2^77 but found no new factors, so still 10 known factors:
http://www.mersenne.org/report_expon...p_hi=566448359

I thought for a moment I found a lot more factors, but apparently mfaktc is not prp checking factors.

(I posted this in the wrong thread first "Mersenne number factored (disbelievers are fools)", so someone can remove the post over there if they want.

[legendarymudkip]

M7508981 ECM B1=50000 bound to should be done by early Tuesday morning.

[VictordeHolland]

Originally Posted by pdazzl

Could you do a B1 between 800000 - 1000000? B2 being 100x of this

Why a B1 between 800,000 - 1,000,000?
Why not take the standard B1 of 1,000,000 for 35 digits factors and run a (coordinated effort of) 1,800 curves (t35)?
To me it would seem easier to keep track of the progress if everybody just used the standard B1 and B2 values.

[Prime95]

Originally Posted by VictordeHolland

Why a B1 between 800,000 - 1,000,000?

If you report your results to Primenet, then the server will convert all effort to the standardized B1 values.

See http://www.mersenne.org/report_ecm/d...nof_hi=7508981

There is nothing wrong with B1=800K-1M, nor is there any problem with jumping straight to 1M.

[R. Gerbicz]

http://www.mersenne.ca/exponent/397 shows that we know 8 factors of 2^397-1 which is clearly wrong as it doesn't give and count the largest factor (p=6597485910270326519900042655193). It looks like an error for all cases where the factorization of 2^n-1 is known, like in trivial cases: http://www.mersenne.ca/exponent/2 : "Known prime factors: None — M2 is prime!"

[pdazzl]

Originally Posted by R. Gerbicz

http://www.mersenne.ca/exponent/397 shows that we know 8 factors of 2^397-1 which is clearly wrong as it doesn't give and count the largest factor (p=6597485910270326519900042655193). It looks like an error for all cases where the factorization of 2^n-1 is known, like in trivial cases: http://www.mersenne.ca/exponent/2 : "Known prime factors: None — M2 is prime!"

I think you're right. There should probably be some logic in the site that gives it +1 on total known factors for numbers that have a PRP cofactor. Though as a straw man argument, one could technically say those numbers(significantly large enough of course) are only prp's and we can't know for sure. But I think that's a relatively moot point.

[pdazzl]

Originally Posted by kracker

I don't know... I currently have 4 cores on it.(can throw more in the fray)

Each curve is 6.2GHz/days. Do you think it would be better if I stepped back on the bounds?

I'm working 200 curves of B1=100000 and will step up from there. If you start at 800000 we can cover more area concurrently; however many curves you want to do.

[kracker]

[Sun Aug 31 11:31:00 2014]
ECM found a factor in curve #1, stage #1
Sigma=117868788464973, B1=900000, B2=90000000.
M7508981 has a factor: 1585181057451124800445697 (ECM curve 1, B1=900000, B2=90000000)
[Sun Aug 31 11:45:07 2014]
ECM found a factor in curve #1, stage #1
Sigma=78442477134346, B1=900000, B2=90000000.
M7508981 has a factor: 1161304516362968943012160629034993307852412903994405213218058778392235296142471 (ECM curve 1, B1=900000, B2=90000000)
[Sun Aug 31 11:58:16 2014]
ECM found a factor in curve #1, stage #1
Sigma=4351222750417745, B1=900000, B2=90000000.
M7508981 has a factor: 9896852950235333792974646943943513 (ECM curve 1, B1=900000, B2=90000000)
ECM found a factor in curve #1, stage #1
Sigma=4531385248127550, B1=900000, B2=90000000.
M7508981 has a factor: 11921519114817291182370230152733598748378993 (ECM curve 1, B1=900000, B2=90000000)

Hmm... what am I doing wrong?

ContinueECM=1 ?