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Groups of continuous transformations of the unit interval and the real line
Lysenko Iryna 1 , Pravitska Natalia 2 , Pratsiovytyi Mykola 3,1 , Ratushniak Sofiya 3,1
1 Department of Higher Mathematics, National Pedagogical Dragomanov University, Kyiv, 01001, Ukraine
2 Department of Algebra and Informatics, Yuriy Fedkovych Chernivtsi National University, Chernivtsi, 58000, Ukraine
3 Department of dynamic systems and fractal analysis, Institute of Mathematics of the National Academy of Sciences of Ukraine, Kyiv, 01001, Ukraine
Keywords: $g$-representation of numbers, left shift operator, right shift operator, set transformation, group of continuous transformations of the unit interval, transformations preserving the tails of number representations
Abstract

This paper is devoted to the study of $g$-representations of real numbers in the unit interval that are topologically equivalent to the classical $s$-adic representation, and continuous transformations of the unit interval associated with such number representations. The transformations under consideration are obtained by gluing together the left and right shift operators of the $g$-representation. While these transformations are piecewise linear in the case of the $s$-adic representation, this property does not hold in general for arbitrary $g$-representations.

It is constructively proved that the set of all continuous transformations of the unit interval preserving the digit frequencies of the $g$-representation, equipped with the operation of composition, forms a noncommutative group of cardinality continuum. A continuum subgroup of this group is formed by the transformations preserving the tails of the $g$-representations of numbers.

References

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Paper Received 7/11/2026
Paper Accepted 7/30/2026
Published Online 8/1/2026
Cite
ACS Style
Lysenko , I.; Pravitska, N.; Pratsiovytyi, M.; Ratushniak, S. Groups of continuous transformations of the unit interval and the real line. Bukovinian Mathematical Journal. 2026, 14 https://doi.org/10.31861/bmj2026.02.01
AMA Style
Lysenko I, Pravitska N, Pratsiovytyi M, Ratushniak S. Groups of continuous transformations of the unit interval and the real line. Bukovinian Mathematical Journal. 2026; 14(2). https://doi.org/10.31861/bmj2026.02.01
Chicago/Turabian Style
Iryna Lysenko , Natalia Pravitska, Mykola Pratsiovytyi, Sofiya Ratushniak. 2026. "Groups of continuous transformations of the unit interval and the real line". Bukovinian Mathematical Journal. 14 no. 2. https://doi.org/10.31861/bmj2026.02.01
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