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Creating Arbitrarily Long Lists of Numbers

Facts about lists of the form 
          (low low+1 ... high)
  1. If low > high, the list is empty,

  2. Otherwise, create it by consing low onto (low+1 ... high) 
     (define integers-from-to
       (lambda (low high)
         (if (> low high)
             '()
             (cons low
                   (integers-from-to (+ 1 low) high)))))
Creating a list by repeatedly consing is called consing up a list. Now try: 
          (integers-from-to 1 2000)

          (integers-from-to 13 37)
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