What to watch
- It takes 15 steps to return to its original phase.
- Most phases remain narrow and readable.
- The two notches control the long cycle.
Oscillators
Pentadecathlon
A slim oscillator with a much longer cycle than its size suggests.
The pentadecathlon is a compact way to show that period length can grow faster than visual complexity.
- Category
- Oscillators
- Period
- 15
- Movement
- bounded
- Population
- 12 cells
- Bounding box
- 3 x 10
- Known since
- 1970
How to use it
Use it to introduce period notation beyond p2 and p3.
Open the pattern in the lab, reduce the speed, and use single-step mode when a phase change is hard to see. The green preview marks births in the next generation; red outlines mark live cells that will die.