Identification Division.
       Program-Id. Indu1.
      * Buch "Verification of Object Oriented Software", 2007
      * Proving by Induction, p458
      * von Angela Wallenberg
       Data Division.
       Working-Storage Section.
         77 i           pic 9(4).
       Linkage Section.
         77 il           pic 9(4).
         77 r            pic 9(4).
       Procedure Division using il returning r.
      * Loop Example
        if i>=0 then
          perform until i<=0
            subtract 1 from i
          end-perform.
        move i to r
       End-Program Indu1.