Fractals

Dragon curve

Order 6. It never crosses itself.

  ┌┐┌┐
  └┼┘└┐
┌┐┌┘ ─┘
└┼┼┐
 └┼┘
  └┐┌┐
┌┐┌┼┼┘
└┼┼┼┼┐┌┐
 └┘└┘└┼┘
      └┐
     │┌┘
     └┘

Hilbert curve

Order 3. It goes through every square exactly once.

│┌─┐┌─┐│
└┘┌┘└┐└┘
┌┐└┐┌┘┌┐
│└─┘└─┘│
└┐┌──┐┌┘
┌┘└┐┌┘└┐
│┌┐││┌┐│
└┘└┘└┘└┘

Sierpinski triangle

Depth 3. Rule 90 makes this one too.

       █
      █ █
     █   █
    █ █ █ █
   █       █
  █ █     █ █
 █   █   █   █
█ █ █ █ █ █ █ █

Rep-tile

Four L-trominoes make a bigger L-tromino.

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