Chapter 1, Building Abstractions with Procedures

Section - Formulating Abstractions with Higher-Order Procedures

Exercise 1.43


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(define (repeated f n)
    (define (repeat rs k)
       (if (= k 1) rs (repeat (compose rs f) (dec k)))
    )
    (repeat f n)
)

Output:

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> ((repeated square 2) 5)
625

As mentioned in the problem we can see that $5^{(2^2)} = 5^4 = 625$ i.e. number five is raised to the $2^n$-th power where $n$ is the number of repetitions.