15. Robert wants to deposit \(\pounds P\) into a savings account. He has a choice of two accounts.
- Account \(A\) offers an annual compound interest rate of \(1 \%\).
- Account \(B\) offers an interest rate of \(5 \%\) for the first year and an annual compound interest rate of \(0.6 \%\) for each subsequent year.
After \(n\) years, account \(A\) is more profitable than account \(B\). Find the smallest value of \(n\).
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