for which all the coefficients \( \alpha_j \)'s are either \(+1\) or \(-1\)
and the functions \( f_j(z) \) are arbitrary analytic functions on
the complex plane.
The functions \( f_j(z) \) can be selected using the pull-down menu above.
The default choice of \( f_j(z) = z^j \) gives us \(n\)-th degree polynomials.
The number of terms, \(n\), can also be changed.