The Existence of Strong Complete Mappings

Abstract

A strong complete mapping of a group $G$ is a bijection $\theta\colon G\to G$ for which both mappings $x\mapsto x\theta(x)$ and $x\mapsto x^{-1}\theta(x)$ are bijections. We characterize finite abelian groups that admit strong complete mappings, thus solving a problem posed by Horton in 1990. We also prove the existence of strong complete mappings for countably infinite groups.

A corrigendum for this paper was added on 2 October 2018.