Dependent automorphisms in prime rings

http://dx.doi.org/10.4153/CMB-1998-059-1
Canad. Math. Bull. 41(1998), 452-462

  Published:1998-12-01
 Printed: Dec 1998

For each $n\geq 4$ we construct a class of examples of a minimal $C$-dependent set of $n$ automorphisms of a prime ring $R$, where $C$ is the extended centroid of $R$. For $n=4$ and $n=5$ it is shown that the preceding examples are completely general, whereas for $n=6$ an example is given which fails to enjoy any of the nice properties of the above example.