We can use the fact that \(2^6 \equiv 1 \pmod{29}\) (which can be easily verified by calculating \(2^6\) and checking that it leaves a remainder of 1 when divided by 29).
So, we have \(2^{23} = 2^{6 \cdot 3 + 5} = (2^6)^3 \cdot 2^5 \equiv 1^3 \cdot 2^5 \equiv 2^5
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