
(/VERSIONCHECK 2) 

(DEFPARAMETER |DifferentialRing;AL| 'NIL) 

(DEFUN |DifferentialRing| ()
  (LET (#:G5031)
    (COND (|DifferentialRing;AL|)
          (T (SETQ |DifferentialRing;AL| (|DifferentialRing;|)))))) 

(DEFUN |DifferentialRing;| ()
  (PROG (#1=#:G5029)
    (RETURN
     (PROG1
         (LETT #1#
               (|Join| (|Ring|)
                       (|mkCategory| '|domain|
                                     '(((|differentiate| ($ $)) T)
                                       ((D ($ $)) T)
                                       ((|differentiate|
                                         ($ $ (|NonNegativeInteger|)))
                                        T)
                                       ((D ($ $ (|NonNegativeInteger|))) T))
                                     NIL '((|NonNegativeInteger|)) NIL))
               |DifferentialRing|)
       (SETELT #1# 0 '(|DifferentialRing|)))))) 

(MAKEPROP '|DifferentialRing| 'NILADIC T) 
