An Elementary Proof for the Decomposition Theorem of Wright Convex Functions

Páles, Zsolt

doi:10.2478/amsil-2020-0010

Abstract

The main goal of this paper is to give a completely elementary proof for the decomposition theorem of Wright convex functions which was discovered by C. T. Ng in 1987. In the proof, we do not use transfinite tools, i.e., variants of Rodé’s theorem, or de Bruijn’s theorem related to functions with continuous differences.

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An Elementary Proof for the Decomposition Theorem of Wright Convex Functions

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