Interesting - if any computer program can be rewritten in the form of a Collatz-like function, is it at all surprising that the BB problems appear in this form?
The interesting part is how simple the resulting Collatz-like functions are to describe, suggesting that the Collatz-like form is the most 'natural' form for hard problems given the TM formalism. E.g., any program can also be rewritten in the form of a Diophantine equation, but most of those would be monstrously large.
