I understand from the Wikipedia page on the Busy Beaver problem that the Busy Beaver values for 5-state 2-symbol (quintuple) Turing-machines have not been determined, because there are 'holdout' machines whose halting behavior is as of yet unknown.Can someone provide me with a concrete example of such a 5-state 2-symbol current (or as close to 'current' as possible) 'holdout'? When looking around on the net, I am finding lots of 'champions', but never any 'holdouts'. Does someone have one or more examples, please?Thanks!EDITTHe linked question asked about 'short programs', but this question is specific to Turing-machines and the Busy Beaver problem. And yes, while that question solicited a response with two Busy Beaver Holdouts of the right kind (Thanks Ricki!), the source provided is 27 years old ... I would like to be able to point to any of these machines and say that these are 'current' holdouts, so if anyone can tell me whether these are still holdouts, or knows of any other, more current, holdouts, I would appreciate it. So, I am holding out for someone who maybe has some more current knowledge regarding the status of these busy beaver holdouts. Thanks!
Wanted: Concrete Example of Busy Beaver Holdout
computability;busy beaver