Rule 90 printed on a navy t-shirt

Rule 090

Single cell

$38.00

GarmentNavy
InkBone
SizeM
Rule90 · 01011010
Initial rowSingle live cell
Lattice161 × 161 cells, periodic
GarmentGildan 64000, 100% ring-spun cotton
PrintDTG front, ~250 dpi, transparent ground
MadeOn demand, printed after you order

Why this rule

Take the XOR of your two neighbours. From a single live cell, that simple instruction draws the Sierpinski triangle without ever being told what a triangle is.