Value distribution of meromorphic functions and their differences

Let f(z) be a transcendental meromorphic function. Results are proved concerning the value distribution of the n'th forward difference Dnf(z), in terms of Borel exceptional values of f(z). The results may be partly viewed as discrete analogues of a classical theorem of Hayman dealing with the possible relationships between Picard exceptional values of f(z) and its derivatives.

Value distribution of meromorphic functions and their differences

Let f(z) be a transcendental meromorphic function. Results are proved concerning the value distribution of the n'th forward difference Dnf(z), in terms of Borel exceptional values of f(z). The results may be partly viewed as discrete analogues of a classical theorem of Hayman dealing with the possible relationships between Picard exceptional values of f(z) and its derivatives.

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  • Ranran ZHANG, Zongxuan CHEN Received: 21.01.2011
  • School of Mathematical Sciences,
  • South China Normal University,
  • Guangzhou 510631, People’s Republic of CHINA
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