I’ve written an implementation of this decider, and an associated verifier, with a formal proof of correctness in Coq for the latter: GitHub - meithecatte/busycoq: Busy Beaver deciders backed by Coq proof
Since in the decider I use an algorithm based on Floyd’s tortoise and hare, it finds slightly less machines when ran with a time limit of 4M, than @TonyG reports.
I also ran it with a time limit of 50M and a space limit of 65536 cells (where the head starts in the middle, so realistically it’s half that).
This gave the following results, after 2.5h:
Translated Cyclers:
73861235 Decided
25 OutOfSpace
480775 OutOfTime
This is 616 more machines than what has been marked as “decided by Translated Cyclers” in the database. This breaks down as follows:
534 backward-reasoning-run-7edeea99bc2d-depth-50-minIndex-0-maxIndex-88664064
10 FAR-finite-automata-reduction-run-JEB-max-6-DFA-states
72 halting-segment-reproduction-run-2vlymsaql86b-max-distance-to-end-6
Unfortunately, nothing newly decided. If it is of any interest, here is the indices file:
newly-decided.dat (2.4 KB)