let x be set ; :: according to VALUED_0:def 11 :: thesis: ( not x in proj1 (r (#) f) or (r (#) f) . x is integer )
assume x in dom (r (#) f) ; :: thesis: (r (#) f) . x is integer
then (r (#) f) . x = r * (f . x) by Def5;
hence (r (#) f) . x is integer ; :: thesis: verum