B. 4803. Is it possible to specify closed intervals of rational endpoints on the number line such that every rational number is the endpoint of exactly one interval, and
\(\displaystyle a)\) one of any pair of closed intervals contains the other;
\(\displaystyle b)\) no pair of two intervals are disjoint, but no interval contains another?
Based on an idea of M. E. Gáspár
Deadline expired on 10 June 2016.