A VERSION OF HILBERT’S 13TH PROBLEM FOR ENTIRE FUNCTIONS

Abstract

It is famous that Hilbert proved that, for any positive integer n, there exists an entire function fn(·, ·, ·) of three complex variables which cannot be represented as any n-time nested superposition constructed from several entire fuctions of two complex variables. In this paper, a finer classification of the 13th problem formulated by Hilbert is given. This classification is applied to the theorem showing that there exists an entire function f(·, ·, ·) of three complex variables which cannot be represented as any finite-time nested superposition constructed from several entire functions of two complex variables. The original result proved by Hilbert can be derived from this theorem.