Re: GCD

Simon> gcd x y is the greatest POSITIVE integer that divides Simon> both x and y.

I find it confusing to read a definition which contains redundant information. Instead, I'd suggest to add something like:

"Note: this number is always positive"

Or, perhaps easier on the eye, "gcd x y is the greatest (positive) integer that divides both x and y." --KW 8-) -- Keith Wansbrough <kw217@cl.cam.ac.uk> http://www.cl.cam.ac.uk/users/kw217/ University of Cambridge Computer Laboratory.