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 doubly exponential time (but is not even known to be computable in ELEMENTARY)
Read more about this topic: Time Complexity
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