Source: cirosantilli/conjecture-reduction-to-a-halting-problem

= Conjecture reduction to a halting problem
{c}

https://bbchallenge.org/story#what-is-known-about-bb lists some (all?) cool examples, 
* BB(15): <Erdős' conjecture on powers of 2>, which has some relation to <Collatz conjecture>
* BB(27): <Goldbach's conjecture>
* BB(744): <Riemann hypothesis>
* BB(748): <independent (mathematical logic)> from the <Zermelo-Fraenkel axioms>
* BB(7910): <independent (mathematical logic)> from the <ZFC>

https://wiki.bbchallenge.org/wiki/Cryptids contains a larger list. In June 2024 it was discovered that <BB(6) is hard>.