Let X be the probability. Let S be the set of points in the integer lattice whose coordinates are relatively prime, so that S occupies a fraction X of the lattice points. This argument is not rigorous, but can be made so. This diagram is to substantiate the claim that every Gaussian integer has a unique bit combination. Large circle is origin.
Dashes indicate continuity of curve at confusing places.
The solid and dotted curves are symmetrical about the point marked with a small circle. 7 is noted. K239 is Mozart's only work for 2 orchestras. Guess what memo this is. And 239 is prime, of course.