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[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

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...

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Let \( d(n) \) denote the number of positive divisors of \( n \). For a positive integer \( n \), we define \( f(n) \) as 

\[ f(n)=d\left(k_{1}\right)+d\left(k_{2}\right)+\ldots+d\left(k_{m}\right) \]

where \( 1 = k_{1} < k_{2} < \cdots < k_{m} = n \) are all divisors of \( n \). We call an integer \( n > 1 \) almost perfect if \( f(n) = n \). Find all almost perfect numbers.

Present the answer in LaTex format: \boxed{Your answer}
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