The number of imaginable ways has no relation to the number of actually possible ways. What we can conceive of is a (very large) superset of that which is possible. The denominator is determined by what is actually possible, not what we can imagine is possible. To put it another way, imagine trying to statistically analyze any ordinary phenomenon where you had to consider not just what is actually possible, but everything you could imagine is possible no matter how absurd. A meaningful analysis will never result from such a standard.