----- SUMMARY FOR THEOREM D-2A2 IN DIRECTORY Q:\D\1 ----- % D-2A2.IN Corrected 1994 April 16 % Left Semi-Distributive Inequality for union over intersection. % Quaife, page 161. formula_list(sos). (all x all y all z (subclass(x,y) -> subclass(union(z,x),union(z,y)))). % LA-3A' % Negation of Semi-Distributive Inequality D-2A2 -(all x all y all z subclass(union(x,intersection(y,z)), intersection(union(x,y),union(x,z)))). end_of_list. ----- Otter 3.0.4, August 1995 ----- The job was started by ??? on ???, Sat Jul 12 03:54:11 1997 Length of proof is 3. Level of proof is 2. ---------------- PROOF ---------------- 208 [] subclass(intersection(x,y),x). 209 [] subclass(intersection(x,y),y). 211 [] -subclass(z,x) | -subclass(z,y) | subclass(z, intersection(x,y)). 215 [] -subclass(x,y) | subclass(union(z,x),union(z,y)). 216 [] -subclass(union($c3,intersection($c2,$c1)), intersection(union($c3,$c2),union($c3,$c1))). 217 [ur,215,209] subclass(union(x,intersection(y,z)),union(x,z)). 218 [ur,215,208] subclass(union(x,intersection(y,z)),union(x,y)). 245 [ur,218,211,217] subclass(union(x,intersection(y,z)), intersection(union(x,y),union(x,z))). 246 [binary,245.1,216.1] $F. ------------ end of proof ------------- clauses generated 112 Kbytes malloced 255 user CPU time 0.33 seconds