Hi,

I’m just starting to learn, or trying to learn Haskell.  I want to write a function to tell me if a number’s prime.  This is what I’ve got:

f x n y = if n>=y

          then True

          else

          if gcd x n == 1

          then f x (n+1) y

          else False

primeQ x = f x 2 y

  where y = floor(sqrt(x))

The compiler is very unhappy.  Apparently there’s some ambiguity in this, and I’m kind of running around in circles.  I’d appreciate any help that will get me started.