Editing Oscillator (cellular automaton) (section)

{{short description|Type of pattern that returns to its original configuration after a number of steps}}
In a [[cellular automaton]], an '''oscillator''' is a pattern that returns to its original state, in the same orientation and position, after a finite number of generations. Thus the evolution of such a pattern repeats itself indefinitely. Depending on context, the term may also include [[spaceship (CA)|spaceship]]s as well. 

An oscillator is considered '''non-trivial''' if it contains at least one cell that oscillates at the necessary period. This means, for example, the mere juxtaposition of a period-17 oscillator and a period-4 oscillator is not a period-68 oscillator.

This article by default considers non-trivial oscillators in [[Conway's Game of Life]], though this concept generalizes to all cellular automata.

The smallest number of generations it takes before the pattern returns to its initial condition is called the ''period'' of the oscillator. An oscillator with a period of 1 is usually called a '''[[still life (cellular automaton)|still life]]''', as such a pattern never changes. Sometimes, still lifes are not taken to be oscillators. Another common stipulation is that an oscillator must be finite.