Description
Fractal made with this old program whose last version is from 2005: Fractal Explorer 2.02 .
The formula used is one of the Sterlingware fornulas included in the program, especifically the formula number 23:
z = z-(z1*z1*c + z1*z + z + c - zsin)/(4*z1*z*c + 3*z1 - zcos)
Raw.