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Continued fractions with low complexity: transcendence measures and quadratic approximation

Published online by Cambridge University Press:  19 March 2012

Yann Bugeaud*
Affiliation:
Mathématiques, Université de Strasbourg, 7, rue René Descartes, 67084 Strasbourg, France (email: [email protected])
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Abstract

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We establish measures of non-quadraticity and transcendence measures for real numbers whose sequence of partial quotients has sublinear block complexity. The main new ingredient is an improvement of Liouville’s inequality giving a lower bound for the distance between two distinct quadratic real numbers. Furthermore, we discuss the gap between Mahler’s exponent w2 and Koksma’s exponent w*2.

Type
Research Article
Copyright
Copyright © Foundation Compositio Mathematica 2012

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