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The Irrationality Exponents of Computable Numbers

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 نشر من قبل Ver\\'onica Becher
 تاريخ النشر 2014
  مجال البحث
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We prove that a real number a greater than or equal to 2 is the irrationality exponent of some computable real number if and only if a is the upper limit of a computable sequence of rational numbers. Thus, there are computable real numbers whose irrationality exponent is not computable.



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