Ok this is getting a bit meta recursive, I made a mistake in the explanation of my mistake that I attempted to edit away before you replied to it. Anyway, I was talking about the range above your range, yo dawg :D...
How if you took a limited precision range of rationals in base 10, e.g 0.10000 to 0.20000 and convert them to base 2, there are "holes" of non-representable numbers in the range. These holes are of different sizes, (one of which is the range you are talking about), so I summarized it as that.