this could be helpful to iterate through tree-like structures. Such as trees. * I was going to mention Calkin-Wilf * discussed below. Conway games also take

this could be helpful to iterate through tree-like structures. Such as trees. * I was going to mention Calkin-Wilf * discussed below. Conway games also take values that are fractions but only dyadic numbers (2^k as denominator) https://en.wikipedia.org/wiki/On_Numbers_and_Games https://en.wikipedia.org/wiki/On_Numbers_and_Games