Gray counter

Gray counter
6bo6b$5bobo5b$4bobobo4b$bo2bo3bo2bob$obobo3bobobo$bo2bo3bo2bob$4bobobo 4b$5bobo5b$6bo! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ AUTOSTART ]] #C [[ TRACKLOOP 4 0 0 GPS 2 THUMBSIZE 2 ]]
View animated image
View static image
Pattern type	Oscillator
Oscillator type	Muttering moat
	Billiard table
Number of cells	26
Bounding box	13 × 9
Period	4
Mod	4
Heat	2
Volatility	0.13
Strict volatility	0.13
Discovered by	Unknown
Year of discovery	1971
Rules Outer-totalistic rules B3/S23 – B378/S0234678 # of rules 27 = 128 Isotropic rules B3iy/S2cik3ceiry – B2ckn34-ejnt5-ejry6-k78/S01c2345-e678
Glider synthesis Fewest gliders 32† Catagolue-generated RLE synthesis Uploaded synthesis RLE graycounter_synth.rle †Can be constructed with 15 gliders using the reverse caber tosser universal constructor.
Pattern files Plaintext graycounter.cells RLE graycounter.rle
Identifiers apgcode xp4_wgiligz25a888a52zx252 Pentadecathlon ID 26P4.3

Gray counter is a period 4 oscillator that was found in 1971. The interior rotor simulates a cycle through the Gray codes from 0 to 3.

The 5-cell long sides of the main part of the stator require induction coils: the option with the smallest population (as well as the highest symmetry) uses two tubs as pictured. A smaller bounding box may be reached using snakes or bi-blocks.

A 30-glider synthesis is known for a stator variant of this oscillator in which one of the tubs is replaced with a boat.

See also

• R2D2

External links

• Gray code at Wikipedia

• Gray counter at the Life Lexicon

• Gray counter at Adam P. Goucher's Catagolue

• 26P4.3 at Heinrich Koenig's Game of Life Object Catalogs