Denominator-preserving maps

Giovanni Panti

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arXiv · 1103.5473

Denominator-preserving maps

Giovanni Panti

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Abstract

Let F be a continuous injective map from an open subset of R^n to R^n. Assume that, for infinitely many k>1, F induces a bijection between the rational points of denominator k in the domain and those in the image (the denominator of (a_1/b_1,...,a_n/b_n) being the l.c.m. of b_1,...,b_n). Then F preserves the Lebesgue measure.

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Giovanni Panti. 2011-05-07. Denominator-preserving maps. https://arxiv.org/abs/1103.5473

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