Purely periodic beta-expansions in the Pisot non-unit case

Valerie Berthe; Anne Siegel

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Purely periodic beta-expansions in the Pisot non-unit case

Valerie Berthe·Anne Siegel

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Abstract

It is well known that real numbers with a purely periodic decimal expansion are the rationals having, when reduced, a denominator coprime with 10. The aim of this paper is to extend this result to beta-expansions with a Pisot base beta which is not necessarily a unit: we characterize real numbers having a purely periodic expansion in such a base; this characterization is given in terms of an explicit set, called generalized Rauzy fractal, which is shown to be a graph-directed self-affine compact subset of non-zero measure which belongs to the direct product of Euclidean and p-adic spaces.

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BibTeX RIS

Valerie Berthe, Anne Siegel. 2004-07-15. Purely periodic beta-expansions in the Pisot non-unit case. https://arxiv.org/abs/math/0407282

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