Abstract
We construct a planar version of the natural extension of the piecewise linear transformation T generating greedy β-expansions with digits in an arbitrary set of real numbers A = {a 0, a 1, a 2}. As a result, we derive in an easy way a closed formula for the density of the unique T-invariant measure µ absolutely continuous with respect to Lebesgue measure. Furthermore, we show that T is exact and weak Bernoulli with respect to µ.
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Dajani, K., Kalle, C. A natural extension for the greedy β-transformation with three arbitrary digits. Acta Math Hung 125, 21–45 (2009). https://doi.org/10.1007/s10474-009-8212-0
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DOI: https://doi.org/10.1007/s10474-009-8212-0