Quote:
Originally Posted by philmoore
GMP is another possibility, it would be interesting to compare with GWNUM on large numbers. Perhaps since Wilfrid Keller would like to see the computation done with two different sets of software, the GCD should be done both ways.

GMP has had a subquadratic GCD for several years now, and even F31size GCDs take only a few hours and < 5GB of memory.