T-tetromino

	T-tetromino
	<a href="/wiki/File:Ttetromino.png" class="image" title="T-tetromino image"><img alt="T-tetromino image" src="/w/images/b/bf/Ttetromino.png" decoding="async" width="81" height="65" /></a>
	<a href="/wiki/File:Ttetromino.png" class="image" title="T-tetromino image"><img alt="T-tetromino image" src="/w/images/b/bf/Ttetromino.png" decoding="async" width="81" height="65" /></a>
	View static image
Pattern type	Miscellaneous
Number of cells	4
Bounding box	3×2
Discovered by	John Conway
Year of discovery	1970
Rules
Outer-totalistic rules	B3/S23 – B37/S02378
Important rules	Conway Life
# of rules	24 = 16
Isotropic rules	B3aeijr/S23aeiy – B2ik34-cew5-e6-n7/S0234-aeinw5-eiy6-c78
Pattern files
Plaintext	ttetromino.cells
RLE	ttetromino.rle

T-tetromino is one of the five tetrominoes. It is a common predecessor of the traffic light, and when paired with another T-tetromino it can become a pre-pulsar.

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 orthogonal spaceship in various isotropic non-totalistic cellular automata, 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.