1-2-3-4

1-2-3-4
x = 11, y = 8, rule = B3/S23 5bo$4bobo$3bobobo$3bo3bo$2obobobob2o$obo5bobo$3b5o$5bo! #C [[ THUMBSIZE 2 THEME 6 GRID GRIDMAJOR 0 SUPPRESS THUMBLAUNCH ]] #C [[ AUTOSTART ]] #C [[ GPS 2 THUMBSIZE 2 ]]
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Pattern type	Oscillator
Oscillator type	Billiard table
Number of cells	25
Bounding box	11 × 8
Period	4 (mod: 4)
Heat	2
Volatility	0.14 | 0.14
Kinetic symmetry	-c
Discovered by	Dean Hickerson
Year of discovery	1989
Rules Outer-totalistic rules B3/S23 – B38/S1235678 # of rules 26 = 64 Isotropic rules B3ery/S2-n3-ajq – B2kn34cikqwyz5-ejry6-ik7c8/S1234-it5678
Glider synthesis Fewest gliders (canonical) 27† Catagolue-generated RLE (canonical) synthesis Fewest gliders (cheapest variant) 8 Catagolue-generated RLE (cheapest variant) synthesis Uploaded synthesis RLE 1234_synth.rle †Can be constructed with 15 gliders using the reverse caber tosser universal constructor.
Pattern files Plaintext 1234.cells RLE 1234.rle
Identifiers apgcode (canonical) xp4_c84q2b2q48czx12521 apgcode (cheapest variant) xp4_69abaab96z69bo5ob96 Pentadecathlon ID 25P4.4

1-2-3-4 is a period-4 oscillator and billiard table configuration found by Dean Hickerson in August 1989. A 24-glider synthesis is known for a stator variant of this oscillator in which the bottom edge is stabilized by a tub, while a 27-glider synthesis was found for the canonical version by Martin Grant in May 2021.

Since its rotor is comprised of one of the two gutter-separated 'lobes' of Achim's p4, the cheapest variant, costing 8 gliders comes from deactivating one lobe with a 3-glider component. This variant has also occurred naturally.

See also

• Achim's p4
• Gray counter
• R2-D2

External links

• 1-2-3-4 at the Life Lexicon

• 25P4.4 at Heinrich Koenig's Game of Life Object Catalogs

• 1-2-3-4 at Adam P. Goucher's Catagolue