TMBR: September 2025
Prev: August 2025 | This Month in Beaver Research | Next: October 2025 |
This Month in Beaver Research for September 2025.
Cryptids
Holdouts
- BB(6):
- Andrew Ducharme and @mxdys both found a family of 10 halting TMs independently, all halting in around steps.
- @mxdys decided two machines’ fates from the 50 Random Holdouts released in August, making 8/50 machined solved as of this month.
- Andrew Ducharme found a non-halting TM, to which Peacemaker II replied with another machine that turned out to be very similar, and non-halting as well. Later in his search Andrew found another non-halting TM.
- BB(7): Andrew Ducharme has continued reducing the number of holdouts, from 59,727,905 to 28,543,434 (52.22% reduction)
- BB(2,6): First, Andrew Ducharme has continued reducing the number of holdouts from 18,054,938 to 17,629,828 (2.35% reduction). Then Terry Ligocki shared that he ran 14 of @mxdys deciders on the holdouts list, reducing the holdout count to a flattering 1,300,334 TMs (92.63% reduction). TODO: Error in the original holdouts list, new holdout count when tjligocki reran mxdys deciders but then that contained an error so then tjligocki reran the deciders for the 3rd time on a verified holdouts list consisting of around 20mil TMs.
BB Adjacent
- John Tromp announced on Discord that a 350-bit function now reaches the limit of BMS, an improvement from the previous 404 bits.
TODO: phrasing. Discord source: https://discord.com/channels/960643023006490684/1355653587824283678/1413637783045542038 and https://github.com/tromp/AIT/blob/master/fast_growing_and_conjectures/bms.lam
- TODO: savask shared "Busy Bug Game": https://discord.com/channels/960643023006490684/1362008236118511758/1415723582989930679
Blog Posts
- 12 Sep 2025. Katelyn Doucette. Bugs, Mazes, and the Unreasonably Effective Brady's Algorithm.