A mandelbrot set for pairs of linear maps

The set of points A ( s )= {± 1 ± s ± s 2 ± s 3 ± … for all sequences of + and −}, generically a fractal. For example A (1/3) is the classical Cantor set and A (1/2 + i/2) is a dragon curve. This set of fractals can be classified in terms of an associated Mandelbrot set D = s ∈ : ¦s¦ A(s) is disconnected. The structure of D and its boundary are investigated.