Double exponential time




An algorithm is said to be double exponential time if T(n) is upper bounded by 22poly(n), where poly(n) is some polynomial in n. Such algorithms belong to the complexity class 2-EXPTIME.

Well-known double exponential time algorithms include:

  • Decision procedures for Presburger arithmetic
  • Computing a Gröbner basis (in the worst case)
  • Quantifier elimination on real closed fields takes at least double exponential time, and can be done in this time.

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