= BB(5)
{c}
= Busy beaver function of 5
{synonym}
{title2}
The last value we will likely every know for the <busy beaver function>! BB(6) is likely completely out of reach forever.
By 2023, it had basically been decided by the <The Busy Beaver Challenge> as mentioned at: https://discuss.bbchallenge.org/t/the-30-to-34-ctl-holdouts-from-bb-5/141[], pending only further verification. It is going to be one of those highly computational proofs that will be needed to be <formally verified> for people to finally settle.
As that project beautifully puts it, as of 2023 prior to full resolution, this can be considered the:
\Q[simplest open problem in mathematics]
on the <Busy beaver scale>.