You can submit your own busy or futile beavers.
4 bit addressing (16 byte memory)
This is the category likely most interesting to breadboard-computer-havers.
The program with the longest known 4-bit halting time takes
- 3066 steps if only valid instructions are allowed.
- 3066 steps if invalid instructions are treated like no-ops.
The program with the longest known 4-bit loop cycle has a cycle of
- 16 steps if only valid instructions are allowed.
- 16 steps if invalid instructions are treated like no-ops.
3 bit addressing (8 byte memory)
The program with the longest known 3-bit halting time takes
- 131333 steps if only valid instructions are allowed.
- 131333 steps if invalid instructions are treated like no-ops.
The program with the longest known 3-bit loop cycle has a cycle of
- 132352 steps if only valid instructions are allowed.
- 132352 steps if invalid instructions are treated like no-ops.
2 bit addressing (4 byte memory)
The paper and talk said that the busy beaver was 835, but this was due to two mis-implemented instructions. It should not be possible to improve any further on the top "scores" in this category (unless I made other mistakes). All 4 billion possible programs were tested, though not all were submitted.
The program with the longest known 2-bit halting time takes
- 859 steps if only valid instructions are allowed.
- 859 steps if invalid instructions are treated like no-ops.
The program with the longest known 2-bit loop cycle has a cycle of
- 1079 steps if only valid instructions are allowed.
- 1079 steps if invalid instructions are treated like no-ops.