As a part of my research i have to use the following z-transform in matlab 'filter' function so as to derive the convoluted signal from the original one.
$$\frac{1}{{\rm Li}_{k}(z^{-1}e^{-b})}$$
But since i read that the polylogarithm can be expressed as a function only for specific values of k (k can take many values, not necessarily integers). Can anyone guide me as to how can i use it for my matlab codes. Will i have to derive the FIR. Can it be derived in this case ?