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Challenge goal
There remain 0 machine with 5 states to decide!! 馃コ

We have achieved our goal of proving "BB(5) = 47,176,870":
Here's what's next:
  • We are writing a human-readable paper presenting the BB(5) proof
  • We are working on new busy beaver values such as BB(6) and setting new goals for these
  • We are maintaining busy beaver knowledge through our Discord, forum and wiki
What is this?
Change machine:
Random machine from the seed database:
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From id in the seed database:
Zoology
This zoology is collaborative.
1. Cyclers
e.g: #279,081#4,231,819#4,239,083
2. Translated cyclers
e.g: #59,645,887#15,167,997#59,090,563#63,687,188
3. Bouncers
e.g: #80,747,967#88,427,177#5,228,688#5,608,043
4. Exponential counters
e.g: #11,004,366#10,936,909#3,840,180
5. Bells
e.g: #8,527,536#73,261,028#63,938,734
Not classified yet:
e.g: #4,446,642#7,410,754#43,374,927
Highlighted machines
Interesting machines:
路聽"inverted counter" [bbchallenge, 2023]
路聽"helix" [bbchallenge, 2023]
路聽"pointy wide" [bbchallenge, 2023]
路聽"complex counter" [Marxen & Buntrock, 1990]
路聽Machine #7,410,754
路聽Machine #2,977,651
路聽Machine #9,005,190
路聽Machine #43,374,927
路聽Machine #14,263,231
路聽Machine #36,909,813
BB champions and other halting machines:
路聽2,133,492-halter [bbchallenge, 2021]
路聽23,554,764-halter [bbchallenge, 2021]
路聽BB(5): 47,176,870-halter [Marxen & Buntrock, 1990]
路聽BB(6): 1015\simeq 10\uparrow\uparrow 15-halter [Kropitz, 2022]
路聽Skelet's machine 1 鈮 Machine #68,329,601
路聽Skelet's machine 17 鈮 Machine #1,365,166