the boundary of bounded orbits, $z \mapsto z^2 + c$
Plate X
Centre−0.50, 0.00
Zoom1×
Iterations120
A point $c$ is inked when the orbit of $z\mapsto z^2+c$ stays bounded;
the shading counts how long the rest take to escape.
After B. Mandelbrot · “Les objets fractals”, 1975