Computable functions of reals

نویسندگان

  • Katrin Tent
  • Martin Ziegler
  • Ralf Schindler
چکیده

We introduce a new notion of computable function on R and prove some basic properties. We give two applications, first a short proof of Yoshinaga’s theorem that periods are elementary (they are actually lower elementary). We also show that the lower elementary complex numbers form an algebraically closed field closed under exponentiation and some other special functions.

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تاریخ انتشار 2009