GMP-ECM vs mprime for F12?

[Xyzzy]

Originally Posted by Prime95

Maybe Xyzzy can dig up the sigma and bounds for his discovered factor.

https://caramel.loria.fr/f12.txt

[GP2]

Originally Posted by Prime95

Maybe Xyzzy can dig up the sigma and bounds for his discovered factor.

FactorDB sometimes has this information, for instance via here or or directly here and click to expand the "ECM" bar.

[WraithX]

Originally Posted by mathwiz

Seems fine to me? Everything builds fine with the latest source...

GMP-ECM 7.0.4 [configured with GMP 6.1.2, GWNUM 29.4, --enable-asm-redc] [ECM]

Could you let me know how you compiled the code? I've tried on Windows (with msys2, mingw64, gmp 6.1.2, gmp-ecm 7.0.4 and latest svn 3039, and gwnum 29.4 and 29.6) and a friend has tried building on Linux and we both get an error during the build process. We get an "undefined reference to 'gwnum_ecmStage1_u64'" when building gmp-ecm. Also there were a few build errors in gmp-ecm that have been fixed in the latest gmp-ecm svn repository.

Did you encounter the undefined reference error? If so, how did you fix it? I've looked inside my gwnum.a library file with the nm tool and I can see that the function is defined in there, so I'm not sure why the compiler is complaining it can't find it.

[mathwiz]

Originally Posted by WraithX

Could you let me know how you compiled the code? I've tried on Windows (with msys2, mingw64, gmp 6.1.2, gmp-ecm 7.0.4 and latest svn 3039, and gwnum 29.4 and 29.6) and a friend has tried building on Linux and we both get an error during the build process. We get an "undefined reference to 'gwnum_ecmStage1_u64'" when building gmp-ecm. Also there were a few build errors in gmp-ecm that have been fixed in the latest gmp-ecm svn repository.

Did you encounter the undefined reference error? If so, how did you fix it? I've looked inside my gwnum.a library file with the nm tool and I can see that the function is defined in there, so I'm not sure why the compiler is complaining it can't find it.

I believe I just did:

./configure  --with-gwnum=$HOME/math/p95/gwnum --with-gmp=/usr/local

after "make -f make64" in gwnum. I downloaded gmp-ecm 7.0.4 from the latest released tarball, rather than checking out the code from svn.

[hansl]

Hi, I'm new to factoring and interested in attempting to tackle F12 also.
I mentioned it a little bit in the How to get started with factoring thread, but just found this one and figured it would be a better place for this specific discussion.

I am curious if anyone knows the max attempted B1 for pm1 on C1133?

[Prime95]

Originally Posted by hansl

I am curious if anyone knows the max attempted B1 for pm1 on C1133?

No, but I am sure it is HUGE. ECM is the way to go -- and you'll need a lot of luck.