Antoine Lucas, Immanuel Scholz, Rainer Boehme <rb-gmp@reflex-studio.de>,
  Sylvain Jasson <Sylvain.Jasson@inrae.fr>,
  Martin Maechler <maechler@stat.math.ethz.ch>
Multiple Precision Arithmetic (big integers and rationals,
 prime number tests, matrix computation), "arithmetic without limitations"
 using the C library GMP (GNU Multiple Precision Arithmetic).
not available, as we use data/*.R *and* our classes