ex f1, f2 being FinSequence of (TOP-REAL 2) st
( f1 is being_S-Seq & f2 is being_S-Seq & R^2-unit_square = (L~ f1) \/ (L~ f2) & (L~ f1) /\ (L~ f2) = {|[0,0]|,|[1,1]|} & f1 /. 1 = |[0,0]| & f1 /. (len f1) = |[1,1]| & f2 /. 1 = |[0,0]| & f2 /. (len f2) = |[1,1]| )