The "tool" in question is part of the Miracl big number library
(at least that is what the output text looks like). Miracl
can be downloaded from:
--- In email@example.com, "Jay Berg" <jberg@e...> wrote:
> --- In firstname.lastname@example.org, "Robert Sitton \(old\)"
> <rsitton@a...> wrote:
> > Is factor.exe open source?
> There's several versions of it floating around. I'd suggest you
> the search for a good source base at the following URL.
> It's a very good tool for cracking most composites. Of course it
> doesn't work on the "most desired". However it is very good on
> breaking apart composite factors generated by other tools.