Computer Studies of Turing Machine Problems

  title={Computer Studies of Turing Machine Problems},
  author={Shen Lin and Tibor Rado},
  journal={J. ACM},
This paper solves a problem relating to Turing machines arising in connection with the Busy Beaver logical game [21. Specifically, with the help of a computer program, the values of two very well-defined positive integers ~(3) and SH(3) are determined to b~ 6 and 21 respectively. The functions Y2(n) and SH(n), however, are noncomputable fune. tions. 

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On non-computable functions
The construction of non-computable functions used in this paper is based on the principle that a finite, non-empty set of non-negative integers has a largest element. Also, this principle is used