On a Functional Equation (III)

Special cases of the general functional equation

α[β(z)] = γ(z) α(z) (1)

have been considered in earlier papers ([1], [2], [3]). In [1], the case β(z) = z + b was considered in detail. In [2], we have discussed the case when β(z) = az + b, a ≠ 1.