Discussion related to cado-nfs

[paul zimmermann <Paul.Zimmermann@inria.fr>]

       Hi,

> I need to factorise a large number of 250 bits，but when I imput the command 
> in the
> terminal like this:
> ./cado-nfs.py 765467679654377986857432645365476
> and the program return a bug.
> So,I create a parammter file : params.c250,and setting some parameters by 
> myselves,but
> the program became this:
> *
> The program get stuck in there.
> Above all,I can't create a right parameter file for 250-bit's number.
> Or help me how to factorise a 250-bit's number.
> Could you help me?
> (Forgive me my bad english grammer)

your parameter file seems correct, since it seems polynomial selection did 
start.
However, since the current factorization record is RSA-768 of 232 digits, you
have zero chance of factoring a 250-digit number by NFS, unless you have 
zillions
of computers available.

Are you sure your number has two large factors of the same size? Otherwise 
you could
try ECM, or maybe even trial division.

Paul Zimmermann