theorem :: REWRITE3:42

for x, y being object
for E being non empty set
for u, v being Element of E ^omega
for F being Subset of (E ^omega)
for TS being non empty transition-system over F st not <%> E in rng (dom the Tran of TS) & [[x,u],[y,v]] in ==>.-relation TS holds
len u > len v