The result of evaluating

With permanent-set! as described in exercise 4.51 and if-fail as in exercise 4.52 , what will be the result of evaluating

(let ((pairs '()))
  (if-fail (let ((p (prime-sum-pair '(1 3 5 8) '(20 35 110))))
             (permanent-set! pairs (cons p pairs))
             (amb))
           pairs))

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