si = a,-a,…; a = -0.4-0.2i
Center: 0; Zoom = 0.4
Different values for a generate collisions at different angles. Let d be the angle, defined as a complex number with |d|=1. Let t be a real number. Set a = dt. For large t, typically |t|>1 there are two separated mini brots. The line between the two is roughly perpendicular to d. As t runs from 1 to 0, the two minis come together, collide and combine and eventually become the Mandelbrot set when t = 0. Different angles, d, produce different intermediate shapes.