let T be non empty RelStr ; for A being Subset of T st T is filled holds
for n being Element of NAT holds Finf A,n c= Finf A,(n + 1)
let A be Subset of T; ( T is filled implies for n being Element of NAT holds Finf A,n c= Finf A,(n + 1) )
assume A1:
T is filled
; for n being Element of NAT holds Finf A,n c= Finf A,(n + 1)
let n be Element of NAT ; Finf A,n c= Finf A,(n + 1)
((Finf A) . n) ^f = Finf A,(n + 1)
by Def6;
hence
Finf A,n c= Finf A,(n + 1)
by A1, Th1; verum