On the multiplicity function of ergodic group extensions, II
Volume 116 / 1995
Studia Mathematica 116 (1995), 207-215
DOI: 10.4064/sm-116-3-207-215
Abstract
For an arbitrary set $A ⊆ ℕ^+$ containing 1, an ergodic automorphism T whose set of essential values of the multiplicity function is equal to A is constructed. If A is additionally finite, T can be chosen to be an analytic diffeomorphism on a finite-dimensional torus.