Consider a blackbox function
$$f(x): Z \rightarrow \lbrace 0,1 \rbrace $$
Which inputs an integer and outputs 0 or 1 with bit complexity n.
If the period P of this function satisfies
$$P \in O(2^{n})$$
Can a quantum computer determine the period of this function within $\frac{2}{3}$ probability of correctness in polynomial in $n$ time using polynomial in $n$ space?
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Let me correct this:
the problem is equivalent to asking if Simon's Algorithm or some variant of it can be used to find the period of a function $f: {\lbrace 0,1 \rbrace}^n \rightarrow \lbrace 0,1 \rbrace$