anchor.diff:        (for a :from 1 :below (min c (- p c)))
         (for b = (- p c a))
         (when (pythagorean-triplet-p a b c)
  -        (adjoinf result (sort (list a b c) #'<)
  +        (adjoinf result (sort< (list a b c))
                    :test #'equal)))
       (finally (return result))))
   
  
positive.code: (test p48 (is (= 9110846700 (problem-48))))
  (test p49 (is (= 296962999629 (problem-49))))
  (test p50 (is (= 997651 (problem-50))))
  
  (test p52 (is (= 142857 (problem-52))))
  (test p56 (is (= 972 (problem-56))))
  (test p74 (is (= 402 (problem-74))))
  
  
negative.code:   ;; The series, 1^1 + 2^2 + 3^3 + ... + 10^10 = 10405071317.
    ;;
    ;; Find the last ten digits of the series, 1^1 + 2^2 + 3^3 + ... + 1000^1000.
    (-<> (irange 1 1000)
      (mapcar #'expt <> <>)
      sum
      (mod <> (expt 10 10))))
  