Das Existenzproblem multivalenter Lösungen bei Differentialgleichungen

Abstract

We consider linear differential equations

$$w^{(n)} + \sum\limits_{i = 0}^{n - 1} {\sigma _i w^{(i)} = 0 in |z|}< 1.$$

If the coefficients σi inH ^∞ the solutions of theis equations have only a finite number of zeros and therefore these solutions are multivalent in |z|<1.