Difference between revisions of "T-tetromino"
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'''T-tetromino''' is one of 5 [[Polyomino#Tetrominoes|tetrominoes]]. It is a common [[predecessor]] of the [[traffic light]], and when paired with another T-tetromino it can become a predecessor of the [[pulsar]]. | '''T-tetromino''' is one of 5 [[Polyomino#Tetrominoes|tetrominoes]]. It is a common [[predecessor]] of the [[traffic light]], and when paired with another T-tetromino it can become a predecessor of the [[pulsar]]. | ||
In a cylindrical grid with a width of 6, the T-tetromino is always a [[replicator]]. It copies itself on the 15th and 40th generations of every 40 generations. However, because it leaves behind [[block]]s, [[blinker]]s, and [[spark]]s, it | In a cylindrical grid with a width of 6, the T-tetromino is always a [[replicator]]. It copies itself on the 15th and 40th generations of every 40 generations. However, because it leaves behind [[block]]s, [[blinker]]s, and [[spark]]s, it doesn't cleanly replicate itself until after 200 generations. It acts much the same way as the replicator in [[Highlife]] because the two copies of the T-tetromino appear offset in opposite directions of the original. Also, two replicators will destroy each other if they are next to each other. The T-tetromino replicates orthogonally and 35 cells away from the original. | ||
It is the daughter of the [[T-pentomino]]. | It is the daughter of the [[T-pentomino]]. | ||
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In the non-totalistic automaton [[tlife]], the T-tetromino is an extremely common [[c/5 orthogonal]] spaceship, with the tip of the T being the leading edge. | In the non-totalistic automaton [[tlife]], the T-tetromino is an extremely common [[c/5 orthogonal]] spaceship, with the tip of the T being the leading edge. | ||
In the rule B34tw5y/S23, it acts almost like a two-dimensional replicator, however the copies react with each other to form 4 [[17c/47 orthogonal]] [[glider]] [[rake]]s. A similar reaction happens in wlife (B34w/S23), forming 4 [[2c/5 orthogonal]] [[beehive]] [[puffer]]s. | In the rule B34tw5y/S23, it acts almost like a two-dimensional replicator, however the copies react with each other to form 4 [[17c/47 orthogonal]] [[glider]] [[rake]]s. A similar reaction happens in [[wlife]] (B34w/S23), forming 4 [[2c/5 orthogonal]] [[beehive]] [[puffer]]s. | ||
==See also== | ==See also== | ||
Revision as of 22:28, 15 November 2019
| T-tetromino | |||||||
| View static image | |||||||
| Pattern type | Miscellaneous | ||||||
|---|---|---|---|---|---|---|---|
| Number of cells | 4 | ||||||
| Bounding box | 3 × 2 | ||||||
| Discovered by | John Conway | ||||||
| Year of discovery | 1970 | ||||||
| |||||||
T-tetromino is one of 5 tetrominoes. It is a common predecessor of the traffic light, and when paired with another T-tetromino it can become a predecessor of the pulsar.
In a cylindrical grid with a width of 6, the T-tetromino is always a replicator. It copies itself on the 15th and 40th generations of every 40 generations. However, because it leaves behind blocks, blinkers, and sparks, it doesn't cleanly replicate itself until after 200 generations. It acts much the same way as the replicator in Highlife because the two copies of the T-tetromino appear offset in opposite directions of the original. Also, two replicators will destroy each other if they are next to each other. The T-tetromino replicates orthogonally and 35 cells away from the original.
It is the daughter of the T-pentomino.
In other rules
The T-tetromino exhibits interesting behaviour in other life-like cellular automata. It is a c/4 orthogonal spaceship in 32 totalistic rules, B345/S126 to B345678/S12678, with the tip of the T being the trailing edge; it is also a c/4 orthonal spaceship in various non-totalistic rules, e.g. GlideLife, though it evolves differently.
In the non-totalistic automaton tlife, the T-tetromino is an extremely common c/5 orthogonal spaceship, with the tip of the T being the leading edge.
In the rule B34tw5y/S23, it acts almost like a two-dimensional replicator, however the copies react with each other to form 4 17c/47 orthogonal glider rakes. A similar reaction happens in wlife (B34w/S23), forming 4 2c/5 orthogonal beehive puffers.
See also
External links
- T-tetromino at the Life Lexicon
- T-tetromino (rule b3s2-i34q) at Adam P. Goucher's Catagolue
- T-tetromino (rule b345s126) at Adam P. Goucher's Catagolue
- Glider 26 at David Eppstein's Glider Database