let i be Element of NAT ; :: thesis: for C being non empty being_simple_closed_curve compact non horizontal non vertical Subset of (TOP-REAL 2)
for p being Point of (TOP-REAL 2) st p `1 = ((W-bound C) + (E-bound C)) / 2 & p `2 = inf (proj2 .: ((LSeg ((Gauge C,1) * (Center (Gauge C,1)),1),((Gauge C,1) * (Center (Gauge C,1)),(width (Gauge C,1)))) /\ (Upper_Arc (L~ (Cage C,(i + 1)))))) holds
ex j being Element of NAT st
( 1 <= j & j <= width (Gauge C,(i + 1)) & p = (Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),j )

let C be non empty being_simple_closed_curve compact non horizontal non vertical Subset of (TOP-REAL 2); :: thesis: for p being Point of (TOP-REAL 2) st p `1 = ((W-bound C) + (E-bound C)) / 2 & p `2 = inf (proj2 .: ((LSeg ((Gauge C,1) * (Center (Gauge C,1)),1),((Gauge C,1) * (Center (Gauge C,1)),(width (Gauge C,1)))) /\ (Upper_Arc (L~ (Cage C,(i + 1)))))) holds
ex j being Element of NAT st
( 1 <= j & j <= width (Gauge C,(i + 1)) & p = (Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),j )

let p be Point of (TOP-REAL 2); :: thesis: ( p `1 = ((W-bound C) + (E-bound C)) / 2 & p `2 = inf (proj2 .: ((LSeg ((Gauge C,1) * (Center (Gauge C,1)),1),((Gauge C,1) * (Center (Gauge C,1)),(width (Gauge C,1)))) /\ (Upper_Arc (L~ (Cage C,(i + 1)))))) implies ex j being Element of NAT st
( 1 <= j & j <= width (Gauge C,(i + 1)) & p = (Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),j ) )

assume that
A1: p `1 = ((W-bound C) + (E-bound C)) / 2 and
A2: p `2 = inf (proj2 .: ((LSeg ((Gauge C,1) * (Center (Gauge C,1)),1),((Gauge C,1) * (Center (Gauge C,1)),(width (Gauge C,1)))) /\ (Upper_Arc (L~ (Cage C,(i + 1)))))) ; :: thesis: ex j being Element of NAT st
( 1 <= j & j <= width (Gauge C,(i + 1)) & p = (Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),j )

per cases ( ( L~ (Upper_Seq C,(i + 1)) = Upper_Arc (L~ (Cage C,(i + 1))) & L~ (Lower_Seq C,(i + 1)) = Lower_Arc (L~ (Cage C,(i + 1))) ) or ( L~ (Upper_Seq C,(i + 1)) = Lower_Arc (L~ (Cage C,(i + 1))) & L~ (Lower_Seq C,(i + 1)) = Upper_Arc (L~ (Cage C,(i + 1))) ) ) by Th9;
suppose A3: ( L~ (Upper_Seq C,(i + 1)) = Upper_Arc (L~ (Cage C,(i + 1))) & L~ (Lower_Seq C,(i + 1)) = Lower_Arc (L~ (Cage C,(i + 1))) ) ; :: thesis: ex j being Element of NAT st
( 1 <= j & j <= width (Gauge C,(i + 1)) & p = (Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),j )

set f = Upper_Seq C,(i + 1);
set G = Gauge C,(i + 1);
set l = Center (Gauge C,(i + 1));
set k = width (Gauge C,(i + 1));
A4: ( width (Gauge C,(i + 1)) = len (Gauge C,(i + 1)) & width (Gauge C,1) = len (Gauge C,1) ) by JORDAN8:def 1;
A5: Upper_Seq C,(i + 1) is_sequence_on Gauge C,(i + 1) by Th10;
width (Gauge C,(i + 1)) >= 4 by A4, JORDAN8:13;
then A6: 1 <= width (Gauge C,(i + 1)) by XXREAL_0:2;
then A7: Center (Gauge C,(i + 1)) <= len (Gauge C,(i + 1)) by A4, JORDAN1B:13;
width (Gauge C,1) >= 4 by A4, JORDAN8:13;
then A8: 1 <= width (Gauge C,1) by XXREAL_0:2;
then A9: Center (Gauge C,1) <= len (Gauge C,1) by A4, JORDAN1B:13;
A10: 1 <= Center (Gauge C,(i + 1)) by JORDAN1B:12;
A11: 1 <= Center (Gauge C,1) by JORDAN1B:12;
A12: LSeg ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),1),((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1)))) meets L~ (Upper_Seq C,(i + 1)) by A3, A4, A6, A10, JORDAN1B:13, JORDAN1B:32;
A13: [(Center (Gauge C,(i + 1))),1] in Indices (Gauge C,(i + 1)) by A6, A7, A10, MATRIX_1:37;
[(Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1)))] in Indices (Gauge C,(i + 1)) by A6, A7, A10, MATRIX_1:37;
then consider n being Element of NAT such that
A14: ( 1 <= n & n <= width (Gauge C,(i + 1)) ) and
A15: ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),n) `2 = inf (proj2 .: ((LSeg ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),1),((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1))))) /\ (L~ (Upper_Seq C,(i + 1))))) by A5, A6, A12, A13, Th1;
take n ; :: thesis: ( 1 <= n & n <= width (Gauge C,(i + 1)) & p = (Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),n )
thus ( 1 <= n & n <= width (Gauge C,(i + 1)) ) by A14; :: thesis: p = (Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),n
len (Gauge C,1) >= 4 by JORDAN8:13;
then A16: 1 <= len (Gauge C,1) by XXREAL_0:2;
then A17: p `1 = ((Gauge C,1) * (Center (Gauge C,1)),1) `1 by A1, JORDAN1A:59
.= ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),n) `1 by A4, A14, A16, JORDAN1A:57 ;
A18: 1 <= i + 1 by NAT_1:11;
(LSeg ((Gauge C,1) * (Center (Gauge C,1)),1),((Gauge C,1) * (Center (Gauge C,1)),(width (Gauge C,1)))) /\ (L~ (Upper_Seq C,(i + 1))) = (LSeg ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),1),((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1))))) /\ (L~ (Upper_Seq C,(i + 1)))
proof
thus (LSeg ((Gauge C,1) * (Center (Gauge C,1)),1),((Gauge C,1) * (Center (Gauge C,1)),(width (Gauge C,1)))) /\ (L~ (Upper_Seq C,(i + 1))) c= (LSeg ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),1),((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1))))) /\ (L~ (Upper_Seq C,(i + 1))) :: according to XBOOLE_0:def 10 :: thesis: (LSeg ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),1),((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1))))) /\ (L~ (Upper_Seq C,(i + 1))) c= (LSeg ((Gauge C,1) * (Center (Gauge C,1)),1),((Gauge C,1) * (Center (Gauge C,1)),(width (Gauge C,1)))) /\ (L~ (Upper_Seq C,(i + 1)))
proof
let a be set ; :: according to TARSKI:def 3 :: thesis: ( not a in (LSeg ((Gauge C,1) * (Center (Gauge C,1)),1),((Gauge C,1) * (Center (Gauge C,1)),(width (Gauge C,1)))) /\ (L~ (Upper_Seq C,(i + 1))) or a in (LSeg ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),1),((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1))))) /\ (L~ (Upper_Seq C,(i + 1))) )
assume A19: a in (LSeg ((Gauge C,1) * (Center (Gauge C,1)),1),((Gauge C,1) * (Center (Gauge C,1)),(width (Gauge C,1)))) /\ (L~ (Upper_Seq C,(i + 1))) ; :: thesis: a in (LSeg ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),1),((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1))))) /\ (L~ (Upper_Seq C,(i + 1)))
then reconsider a1 = a as Point of (TOP-REAL 2) ;
A20: ( a1 in LSeg ((Gauge C,1) * (Center (Gauge C,1)),1),((Gauge C,1) * (Center (Gauge C,1)),(width (Gauge C,1))) & a1 in L~ (Upper_Seq C,(i + 1)) ) by A19, XBOOLE_0:def 4;
((Gauge C,1) * (Center (Gauge C,1)),1) `1 = ((Gauge C,1) * (Center (Gauge C,1)),(width (Gauge C,1))) `1 by A8, A9, A11, GOBOARD5:3;
then A21: a1 `1 = ((Gauge C,1) * (Center (Gauge C,1)),1) `1 by A20, GOBOARD7:5
.= ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),1) `1 by A4, A6, A8, JORDAN1A:57 ;
then A22: a1 `1 = ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1)))) `1 by A6, A7, A10, GOBOARD5:3;
Cage C,(i + 1) is_sequence_on Gauge C,(i + 1) by JORDAN9:def 1;
then A23: ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),1) `2 <= S-bound (L~ (Cage C,(i + 1))) by A4, A6, A10, JORDAN1A:43, JORDAN1B:13;
A24: Upper_Arc (L~ (Cage C,(i + 1))) c= L~ (Cage C,(i + 1)) by JORDAN6:76;
a1 in Upper_Arc (L~ (Cage C,(i + 1))) by A3, A19, XBOOLE_0:def 4;
then a1 `2 >= S-bound (L~ (Cage C,(i + 1))) by A24, PSCOMP_1:71;
then A25: a1 `2 >= ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),1) `2 by A23, XXREAL_0:2;
Cage C,(i + 1) is_sequence_on Gauge C,(i + 1) by JORDAN9:def 1;
then A26: ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1)))) `2 >= N-bound (L~ (Cage C,(i + 1))) by A4, A6, A10, JORDAN1A:41, JORDAN1B:13;
a1 in Upper_Arc (L~ (Cage C,(i + 1))) by A3, A19, XBOOLE_0:def 4;
then a1 `2 <= N-bound (L~ (Cage C,(i + 1))) by A24, PSCOMP_1:71;
then a1 `2 <= ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1)))) `2 by A26, XXREAL_0:2;
then a1 in LSeg ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),1),((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1)))) by A21, A22, A25, GOBOARD7:8;
hence a in (LSeg ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),1),((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1))))) /\ (L~ (Upper_Seq C,(i + 1))) by A20, XBOOLE_0:def 4; :: thesis: verum
end;
thus (LSeg ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),1),((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1))))) /\ (L~ (Upper_Seq C,(i + 1))) c= (LSeg ((Gauge C,1) * (Center (Gauge C,1)),1),((Gauge C,1) * (Center (Gauge C,1)),(width (Gauge C,1)))) /\ (L~ (Upper_Seq C,(i + 1))) by A4, A18, JORDAN1A:65, XBOOLE_1:26; :: thesis: verum
end;
hence p = (Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),n by A2, A3, A15, A17, TOPREAL3:11; :: thesis: verum
end;
suppose A27: ( L~ (Upper_Seq C,(i + 1)) = Lower_Arc (L~ (Cage C,(i + 1))) & L~ (Lower_Seq C,(i + 1)) = Upper_Arc (L~ (Cage C,(i + 1))) ) ; :: thesis: ex j being Element of NAT st
( 1 <= j & j <= width (Gauge C,(i + 1)) & p = (Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),j )

set f = Lower_Seq C,(i + 1);
set G = Gauge C,(i + 1);
set l = Center (Gauge C,(i + 1));
set k = width (Gauge C,(i + 1));
A28: ( width (Gauge C,(i + 1)) = len (Gauge C,(i + 1)) & width (Gauge C,1) = len (Gauge C,1) ) by JORDAN8:def 1;
A29: Lower_Seq C,(i + 1) is_sequence_on Gauge C,(i + 1) by Th12;
width (Gauge C,(i + 1)) >= 4 by A28, JORDAN8:13;
then A30: 1 <= width (Gauge C,(i + 1)) by XXREAL_0:2;
then A31: Center (Gauge C,(i + 1)) <= len (Gauge C,(i + 1)) by A28, JORDAN1B:13;
width (Gauge C,1) >= 4 by A28, JORDAN8:13;
then A32: 1 <= width (Gauge C,1) by XXREAL_0:2;
then A33: Center (Gauge C,1) <= len (Gauge C,1) by A28, JORDAN1B:13;
A34: 1 <= Center (Gauge C,(i + 1)) by JORDAN1B:12;
A35: 1 <= Center (Gauge C,1) by JORDAN1B:12;
A36: LSeg ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),1),((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1)))) meets L~ (Lower_Seq C,(i + 1)) by A27, A28, A30, A34, JORDAN1B:13, JORDAN1B:32;
A37: [(Center (Gauge C,(i + 1))),1] in Indices (Gauge C,(i + 1)) by A30, A31, A34, MATRIX_1:37;
[(Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1)))] in Indices (Gauge C,(i + 1)) by A30, A31, A34, MATRIX_1:37;
then consider n being Element of NAT such that
A38: ( 1 <= n & n <= width (Gauge C,(i + 1)) ) and
A39: ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),n) `2 = inf (proj2 .: ((LSeg ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),1),((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1))))) /\ (L~ (Lower_Seq C,(i + 1))))) by A29, A30, A36, A37, Th1;
take n ; :: thesis: ( 1 <= n & n <= width (Gauge C,(i + 1)) & p = (Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),n )
thus ( 1 <= n & n <= width (Gauge C,(i + 1)) ) by A38; :: thesis: p = (Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),n
len (Gauge C,1) >= 4 by JORDAN8:13;
then A40: 1 <= len (Gauge C,1) by XXREAL_0:2;
then A41: p `1 = ((Gauge C,1) * (Center (Gauge C,1)),1) `1 by A1, JORDAN1A:59
.= ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),n) `1 by A28, A38, A40, JORDAN1A:57 ;
A42: 1 <= i + 1 by NAT_1:11;
(LSeg ((Gauge C,1) * (Center (Gauge C,1)),1),((Gauge C,1) * (Center (Gauge C,1)),(width (Gauge C,1)))) /\ (L~ (Lower_Seq C,(i + 1))) = (LSeg ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),1),((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1))))) /\ (L~ (Lower_Seq C,(i + 1)))
proof
thus (LSeg ((Gauge C,1) * (Center (Gauge C,1)),1),((Gauge C,1) * (Center (Gauge C,1)),(width (Gauge C,1)))) /\ (L~ (Lower_Seq C,(i + 1))) c= (LSeg ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),1),((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1))))) /\ (L~ (Lower_Seq C,(i + 1))) :: according to XBOOLE_0:def 10 :: thesis: (LSeg ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),1),((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1))))) /\ (L~ (Lower_Seq C,(i + 1))) c= (LSeg ((Gauge C,1) * (Center (Gauge C,1)),1),((Gauge C,1) * (Center (Gauge C,1)),(width (Gauge C,1)))) /\ (L~ (Lower_Seq C,(i + 1)))
proof
let a be set ; :: according to TARSKI:def 3 :: thesis: ( not a in (LSeg ((Gauge C,1) * (Center (Gauge C,1)),1),((Gauge C,1) * (Center (Gauge C,1)),(width (Gauge C,1)))) /\ (L~ (Lower_Seq C,(i + 1))) or a in (LSeg ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),1),((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1))))) /\ (L~ (Lower_Seq C,(i + 1))) )
assume A43: a in (LSeg ((Gauge C,1) * (Center (Gauge C,1)),1),((Gauge C,1) * (Center (Gauge C,1)),(width (Gauge C,1)))) /\ (L~ (Lower_Seq C,(i + 1))) ; :: thesis: a in (LSeg ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),1),((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1))))) /\ (L~ (Lower_Seq C,(i + 1)))
then reconsider a1 = a as Point of (TOP-REAL 2) ;
A44: ( a1 in LSeg ((Gauge C,1) * (Center (Gauge C,1)),1),((Gauge C,1) * (Center (Gauge C,1)),(width (Gauge C,1))) & a1 in L~ (Lower_Seq C,(i + 1)) ) by A43, XBOOLE_0:def 4;
((Gauge C,1) * (Center (Gauge C,1)),1) `1 = ((Gauge C,1) * (Center (Gauge C,1)),(width (Gauge C,1))) `1 by A32, A33, A35, GOBOARD5:3;
then A45: a1 `1 = ((Gauge C,1) * (Center (Gauge C,1)),1) `1 by A44, GOBOARD7:5
.= ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),1) `1 by A28, A30, A32, JORDAN1A:57 ;
then A46: a1 `1 = ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1)))) `1 by A30, A31, A34, GOBOARD5:3;
Cage C,(i + 1) is_sequence_on Gauge C,(i + 1) by JORDAN9:def 1;
then A47: ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),1) `2 <= S-bound (L~ (Cage C,(i + 1))) by A28, A30, A34, JORDAN1A:43, JORDAN1B:13;
A48: Upper_Arc (L~ (Cage C,(i + 1))) c= L~ (Cage C,(i + 1)) by JORDAN6:76;
a1 in Upper_Arc (L~ (Cage C,(i + 1))) by A27, A43, XBOOLE_0:def 4;
then a1 `2 >= S-bound (L~ (Cage C,(i + 1))) by A48, PSCOMP_1:71;
then A49: a1 `2 >= ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),1) `2 by A47, XXREAL_0:2;
Cage C,(i + 1) is_sequence_on Gauge C,(i + 1) by JORDAN9:def 1;
then A50: ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1)))) `2 >= N-bound (L~ (Cage C,(i + 1))) by A28, A30, A34, JORDAN1A:41, JORDAN1B:13;
a1 in Upper_Arc (L~ (Cage C,(i + 1))) by A27, A43, XBOOLE_0:def 4;
then a1 `2 <= N-bound (L~ (Cage C,(i + 1))) by A48, PSCOMP_1:71;
then a1 `2 <= ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1)))) `2 by A50, XXREAL_0:2;
then a1 in LSeg ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),1),((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1)))) by A45, A46, A49, GOBOARD7:8;
hence a in (LSeg ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),1),((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1))))) /\ (L~ (Lower_Seq C,(i + 1))) by A44, XBOOLE_0:def 4; :: thesis: verum
end;
thus (LSeg ((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),1),((Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),(width (Gauge C,(i + 1))))) /\ (L~ (Lower_Seq C,(i + 1))) c= (LSeg ((Gauge C,1) * (Center (Gauge C,1)),1),((Gauge C,1) * (Center (Gauge C,1)),(width (Gauge C,1)))) /\ (L~ (Lower_Seq C,(i + 1))) by A28, A42, JORDAN1A:65, XBOOLE_1:26; :: thesis: verum
end;
hence p = (Gauge C,(i + 1)) * (Center (Gauge C,(i + 1))),n by A2, A27, A39, A41, TOPREAL3:11; :: thesis: verum
end;
end;