Approximations to the Halting Problem

نویسنده

  • Nancy A. Lynch
چکیده

The halting set Kr = (x I r converges}, for any G6del numbering ~ = {~0, ~1 ,-..}, is nonrecursive. It may be possible, however, to approximate Kr by recursive s e t s . We note several results indicating that the degrees of recursive approximability of halting sets in arbitrary GSdel numberings have wide variation, while restriction to "optimal GSdel numberings" only narrows the possibilities slightly.

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عنوان ژورنال:
  • J. Comput. Syst. Sci.

دوره 9  شماره 

صفحات  -

تاریخ انتشار 1974