Quelle  iterative.cob   Sprache: Cobol

       identification division.
       program-id. iterative.
      * aus Adamek/Milius/Vielebi
      * From iterative algebras
      * to iterative theories
      * example (1.2)
       author. "JD".
       date-written. 27.3.2009.
       date-compiled.
       data division.
       working-storage section.
       77 s pic 9(4).
       linkage section.
       77 x1   pic 9(4).
       77 x2   pic 9(4).
       77 t    pic 9(4).
       procedure division using x1 x2 t.
         perform until x1 <= 0
           compute x1 = x2*t
           compute x2 = (x1*s)*t
         end-perform.
        end-program  iterative.