let T be non empty RelStr ; for p being Element of T
for k being Element of NAT st T is filled holds
U_FT p,k c= U_FT p,(k + 1)
let p be Element of T; for k being Element of NAT st T is filled holds
U_FT p,k c= U_FT p,(k + 1)
let k be Element of NAT ; ( T is filled implies U_FT p,k c= U_FT p,(k + 1) )
A1:
U_FT p,(k + 1) = (U_FT p,k) ^f
by FINTOPO3:48;
assume
T is filled
; U_FT p,k c= U_FT p,(k + 1)
hence
U_FT p,k c= U_FT p,(k + 1)
by A1, FINTOPO3:1; verum