This archive contains an Installer.app package for pari-1.39. I built a
(quad-FAT) portable c++ version first, then built an optimized assembly
i386 version, and lipo'd in the faster (about 15%-40% faster) i386 into
the FAT binary gp.
Initial tests (tested only on m68k and i386) show the i386 version (both c++
and assembly) to be relatively stable, whereas the m68k version is not as so.
Your mileage may vary...
From the PARI manual, Introduction:
The PARI system is a package which is capable of doing formal computations on recursive types at high speed; it is primarily aimed at number theorists, but can be used by people who primary need is speed.
Although quite an amount of symbolic manipulation is possible in PARI, this
system does very badly compared to much more sophisticated systems like
Axiom, Macsyma, Magma, Maple, Mathematica or Reduce on such