[cellular-automata.git] / seeds / README.md

Seeds
=====

https://en.wikipedia.org/wiki/Seeds_(cellular_automaton)

> Seeds is a cellular automaton in the same family as the Game of Life,
> initially investigated by Brian Silverman[1][2] and named by Mirek
> Wójtowicz.[1][3] It consists of infinite two-dimensional grid of cells, each
> of which may be in one of two states: on or off. Each cell is considered to
> have eight neighbors (Moore neighborhood), as in Life. In each time step, a
> cell turns on or is "born" if it was off or "dead" but had exactly two
> neighbors that were on; all other cells turn off. Thus, in the notation
> describing the family of cellular automata containing Life, it is described
> by the rule B2/S.[1]
>
> In Game of Life terminology, a pattern in which all cells that were on turn
> off at each step is called a phoenix. All patterns in Seeds have this form.
> Even though all live cells are constantly dying, the small birth requirement
> of two cells means that nearly every pattern in Seeds explodes into a chaotic
> mess that grows to cover the entire universe. Thus, in Wolfram's
> classification of cellular automata, it is a Class III automaton, in which
> nearly all patterns evolve chaotically.[1]
>
> However, some patterns are known to behave in a more controlled fashion,
> repeating the same shape either in the same position of the grid (an
> oscillator) or translated some number of grid units after several steps (a
> spaceship). More complex rake and puffer patterns are known which move like
> spaceships leaving trails of oscillators or other spaceships behind them.
> Most of these patterns move at a speed of 1 cell per time step (the so-called
> speed of light, or c/1)[4] including three commonly seen spaceships with four
> on cells each, but slower-moving patterns are also known. A collection of
> patterns for the Seeds rule collected by Jason Summers includes patterns
> found by Stephen Wright, Mirek Wójtowicz, Noam Elkies, Mark Niemiec, Peter
> Naszvadi, and David Eppstein.[5]
Commit	Line	Data
a5bb74bc SK	1	Seeds
	2	=====
	3
	4	https://en.wikipedia.org/wiki/Seeds_(cellular_automaton)
	5
	6	> Seeds is a cellular automaton in the same family as the Game of Life,
	7	> initially investigated by Brian Silverman[1][2] and named by Mirek
	8	> Wójtowicz.[1][3] It consists of infinite two-dimensional grid of cells, each
	9	> of which may be in one of two states: on or off. Each cell is considered to
	10	> have eight neighbors (Moore neighborhood), as in Life. In each time step, a
	11	> cell turns on or is "born" if it was off or "dead" but had exactly two
	12	> neighbors that were on; all other cells turn off. Thus, in the notation
	13	> describing the family of cellular automata containing Life, it is described
	14	> by the rule B2/S.[1]
	15	>
	16	> In Game of Life terminology, a pattern in which all cells that were on turn
	17	> off at each step is called a phoenix. All patterns in Seeds have this form.
	18	> Even though all live cells are constantly dying, the small birth requirement
	19	> of two cells means that nearly every pattern in Seeds explodes into a chaotic
	20	> mess that grows to cover the entire universe. Thus, in Wolfram's
	21	> classification of cellular automata, it is a Class III automaton, in which
	22	> nearly all patterns evolve chaotically.[1]
	23	>
	24	> However, some patterns are known to behave in a more controlled fashion,
	25	> repeating the same shape either in the same position of the grid (an
	26	> oscillator) or translated some number of grid units after several steps (a
	27	> spaceship). More complex rake and puffer patterns are known which move like
	28	> spaceships leaving trails of oscillators or other spaceships behind them.
	29	> Most of these patterns move at a speed of 1 cell per time step (the so-called
	30	> speed of light, or c/1)[4] including three commonly seen spaceships with four
	31	> on cells each, but slower-moving patterns are also known. A collection of
	32	> patterns for the Seeds rule collected by Jason Summers includes patterns
	33	> found by Stephen Wright, Mirek Wójtowicz, Noam Elkies, Mark Niemiec, Peter
	34	> Naszvadi, and David Eppstein.[5]