I'm getting caught up in the notation here. Not entirely sure what it is saying. My interpretation: (a,b) is an element of (the binary product) N x N then this "|" trips me up My guess: the "a" element in the set is less than the b, the b is less than or equal to 3. Set B = (the notation for rational numbers) "|" a,b is an element in the set (-1, 1, 2)).
I think my biggest problem is with these "|" and what they mean.
