Spiky Growth
From Softology's collection · B13,17,20-26/S0-3,7-9,11-13,18,21-22,24,26/C4
Noise hardens into spiky clumps within a few generations.
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 13, 17 or 20 to 26 of its neighbours are alive.
- A live cell stays alive when 0 to 3, 7 to 9, 11 to 13, 18, 21, 22, 24 or 26 of its neighbours are alive; otherwise it starts dying: for 2 generations it fades, is not counted as a neighbour and blocks births, then the cell is empty again.
- With 4 states in all (alive, 2 dying, dead), this is a Generations rule.
Picking it in the app restarts the world from a random fill with 15% of cells alive. 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 | B13,17,20-26/S0-3,7-9,11-13,18,21-22,24,26/C4 |
|---|---|
| Softology, MCell (S/B/C/N) | 0-3,7-9,11-13,18,21-22,24,26/13,17,20-26/4/M |
| 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 of Softology's rules
- 445
B4/S4/C5 - Amoeba
B5-7,12-13,15/S9-26/C5 - Architecture
B3/S4-6 - Builder 1
B4,6,8-9/S2,6,9/C10 - Builder 2
B1/S5-7 - Clouds 1
B13-14,17-19/S13-26 - Clouds 2
B13-14/S12-26 - Coral
B6-7,9,12/S5-8/C4 - Crystal Growth 1
B1,3/S0-6 - Crystal Growth 2
B1,3/S1-2/C5 - Pyroclastic
B6-8/S4-7/C10 - 3D Brain
B4/S
All 30 rules · From 2D to 3D: why Conway's rule needs changing in 3D