def anish_astakh(XYZ, t, u=1.2, n=0.5):
    """
    The Anishenko-Astakhov Attractor.
    x0 = (0.1,0,0)
    """
    x, y, z = XYZ
    i = 1 if x >= 0 else 0
    x_dt = u * x + y - x * z
    y_dt = -x
    z_dt = -n * z + n * i * x**2
    return x_dt, y_dt, z_dt