  The tree based representation described in this paper, hereditarily binary
numbers, applies recursively a run-length compression mechanism that enables
computations limited by the structural complexity of their operands rather than
by their bitsizes. While within constant factors from their traditional
counterparts for their worst case behavior, our arithmetic operations open the
doors for interesting numerical computations, impossible with traditional
number representations. We provide a complete specification of our algorithms
in the form of a purely declarative Prolog program.
