Stable
Classic rule · B4/S4-5
Despite its name, a random block grows until about a fifth of the box churns; solid shapes die at once.
How the rule works
- Each cell has 26 neighbours: every cell that shares a face, an edge or a corner with it (the Moore neighbourhood).
- An empty cell comes alive when exactly 4 of its neighbours are alive.
- A live cell stays alive when 4 or 5 of its neighbours are alive; otherwise it dies.
Picking it in the app restarts the world from a random block in the middle of the box, 50% full and a third as wide as the box. Its seed is fixed, so it is the same world every time, one still alive 40 generations later in the default 15×15×15 box; N tries another seed.
Notation
| Birth/survival | B4/S4-5 |
|---|---|
| Softology, MCell (S/B/C/N) | 4-5/4/2/M |
| Weighted counting | B12/S12,15 (faces count 3, edges 2, corners 1) |
| Neighbourhood | Moore (26 cells) |
B lists the neighbour counts at which an empty cell is born, S those at which a live cell survives, and C the number of states. How to read a rule
More classic rules
- Standard
B4-5/S4-6 - Chaotic
B3-6/S2-5 - Die-Off
B5-6/S5-6 - Explosive
B2-6/S1-6 - Crystal
B5/S3-5 - Pulsating
B4-6/S3-4 - Maze
B3-4/S3-4 - Sparse
B6/S5
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