theorem :: JORDAN5C:28
for f being FinSequence of (TOP-REAL 2)
for Q being Subset of (TOP-REAL 2)
for q being Point of (TOP-REAL 2)
for i, j being Nat st L~ f meets Q & f is being_S-Seq & Q is closed & Last_Point ((L~ f),(f /. 1),(f /. (len f)),Q) in LSeg (f,i) & 1 <= i & i + 1 <= len f & q in LSeg (f,j) & 1 <= j & j + 1 <= len f & q in Q & Last_Point ((L~ f),(f /. 1),(f /. (len f)),Q) <> q holds
( i >= j & ( i = j implies LE q, Last_Point ((L~ f),(f /. 1),(f /. (len f)),Q),f /. i,f /. (i + 1) ) )