1-2-3

	1-2-3
	<a href="/wiki/File:123.png" class="image" title="1-2-3 image"><img alt="1-2-3 image" src="/w/images/8/81/123.png" decoding="async" width="97" height="89" /></a>
	<a href="/wiki/File:123.png" class="image" title="1-2-3 image"><img alt="1-2-3 image" src="/w/images/8/81/123.png" decoding="async" width="97" height="89" /></a>
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Pattern type	Oscillator
Oscillator type	Muttering moat
	Billiard table
Number of cells	26
Bounding box	10 × 9
Period	3 (mod: 3)
Heat	2
Volatility	0.11 \| 0.11
Kinetic symmetry	n
Rotor type	1-2-3
Discovered by	David Buckingham
Year of discovery	1972
Rules
Outer-totalistic rules	B3/S23 – B378/S0235678
# of rules	27 = 128
Isotropic rules	B3jn/S2-cn3-eiq – B2in34ceky5ceiq6cen78/S01c234-ik5678
Glider synthesis
Fewest gliders (canonical)	57†
Catagolue-generated RLE (canonical)	synthesis
Fewest gliders (cheapest variant)	53†
Catagolue-generated RLE (cheapest variant)	synthesis
	†Can be constructed with 15 gliders using the reverse caber tosser universal constructor.
Pattern files
Plaintext	123.cells
RLE	123.rle
Identifiers
apgcode (canonical)	xp3_g0gbb8oz11078aqi6
apgcode (cheapest variant)	xp3_6s17o4s0cczw11da1

1-2-3 was found by David Buckingham in August 1972.^[1] This is one of only three essentially different period-3 oscillators with only three cells in the rotor. The others are stillater and cuphook.

A 69-glider synthesis is known for a stator variant^[2] of this oscillator and was discovered by Martin Grant.^[3] It has since been reduced to a 53-glider synthesis in its cheapest form.

References

↑ Dean Hickerson's oscillator stamp collection. Retrieved on March 14, 2020.
↑ xp3_6s17o4s0cczw11da1
↑ Martin Grant (December 27, 2015). Re: Synthesising Oscillators (discussion thread) at the ConwayLife.com forums