let f be non constant standard special_circular_sequence; :: thesis: (W-min (L~ f)) `2 < (W-max (L~ f)) `2
set p = W-min (L~ f);
set i = (W-min (L~ f)) .. f;
A1: len f > 3 + 1 by GOBOARD7:36;
A2: len f >= 1 + 1 by GOBOARD7:36, XXREAL_0:2;
A3: W-min (L~ f) in rng f by Th47;
then A4: (W-min (L~ f)) .. f in dom f by FINSEQ_4:30;
then A5: ( 1 <= (W-min (L~ f)) .. f & (W-min (L~ f)) .. f <= len f ) by FINSEQ_3:27;
A6: W-min (L~ f) = f . ((W-min (L~ f)) .. f) by A3, FINSEQ_4:29
.= f /. ((W-min (L~ f)) .. f) by A4, PARTFUN1:def 8 ;
A7: (W-min (L~ f)) `1 = W-bound (L~ f) by EUCLID:56;
per cases ( (W-min (L~ f)) .. f = 1 or (W-min (L~ f)) .. f = len f or ( 1 < (W-min (L~ f)) .. f & (W-min (L~ f)) .. f < len f ) ) by A5, XXREAL_0:1;
suppose A8: ( (W-min (L~ f)) .. f = 1 or (W-min (L~ f)) .. f = len f ) ; :: thesis: (W-min (L~ f)) `2 < (W-max (L~ f)) `2
then W-min (L~ f) = f /. 1 by A6, FINSEQ_6:def 1;
then A9: W-min (L~ f) in LSeg f,1 by A2, TOPREAL1:27;
A10: 1 + 1 in dom f by A2, FINSEQ_3:27;
then A11: f /. (1 + 1) in L~ f by A1, GOBOARD1:16, XXREAL_0:2;
A12: f /. (1 + 1) in LSeg f,1 by A2, TOPREAL1:27;
A13: ((len f) -' 1) + 1 = len f by A1, XREAL_1:237, XXREAL_0:2;
then (len f) -' 1 > 3 by A1, XREAL_1:8;
then A14: (len f) -' 1 > 1 by XXREAL_0:2;
then A15: f /. ((len f) -' 1) in LSeg f,((len f) -' 1) by A13, TOPREAL1:27;
(len f) -' 1 <= len f by A13, NAT_1:11;
then A16: (len f) -' 1 in dom f by A14, FINSEQ_3:27;
then A17: f /. ((len f) -' 1) in L~ f by A1, GOBOARD1:16, XXREAL_0:2;
A18: f /. 1 = f /. (len f) by FINSEQ_6:def 1;
then A19: W-min (L~ f) in LSeg f,((len f) -' 1) by A6, A8, A13, A14, TOPREAL1:27;
A20: 1 in dom f by FINSEQ_5:6;
then A21: W-min (L~ f) <> f /. (1 + 1) by A6, A8, A18, A10, GOBOARD7:31;
A22: len f in dom f by FINSEQ_5:6;
then A23: W-min (L~ f) <> f /. ((len f) -' 1) by A6, A8, A18, A13, A16, GOBOARD7:31;
A24: ( not LSeg f,((len f) -' 1) is horizontal or not LSeg f,1 is horizontal )
proof
assume ( LSeg f,((len f) -' 1) is horizontal & LSeg f,1 is horizontal ) ; :: thesis: contradiction
then A25: ( (W-min (L~ f)) `2 = (f /. (1 + 1)) `2 & (W-min (L~ f)) `2 = (f /. ((len f) -' 1)) `2 ) by A19, A9, A15, A12, SPPOL_1:def 2;
A26: ( (f /. (1 + 1)) `1 <= (f /. ((len f) -' 1)) `1 or (f /. (1 + 1)) `1 >= (f /. ((len f) -' 1)) `1 ) ;
A27: ( (W-min (L~ f)) `1 <= (f /. (1 + 1)) `1 & (W-min (L~ f)) `1 <= (f /. ((len f) -' 1)) `1 ) by A7, A17, A11, PSCOMP_1:71;
( LSeg f,1 = LSeg (f /. 1),(f /. (1 + 1)) & LSeg f,((len f) -' 1) = LSeg (f /. 1),(f /. ((len f) -' 1)) ) by A2, A18, A13, A14, TOPREAL1:def 5;
then ( f /. ((len f) -' 1) in LSeg f,1 or f /. (1 + 1) in LSeg f,((len f) -' 1) ) by A6, A8, A18, A25, A27, A26, GOBOARD7:9;
then ( f /. ((len f) -' 1) in (LSeg f,((len f) -' 1)) /\ (LSeg f,1) or f /. (1 + 1) in (LSeg f,((len f) -' 1)) /\ (LSeg f,1) ) by A15, A12, XBOOLE_0:def 4;
then A28: (LSeg f,((len f) -' 1)) /\ (LSeg f,1) <> {(f /. 1)} by A6, A8, A18, A23, A21, TARSKI:def 1;
f . 1 = f /. 1 by A20, PARTFUN1:def 8;
hence contradiction by A28, JORDAN4:54; :: thesis: verum
end;
now
per cases ( LSeg f,((len f) -' 1) is vertical or LSeg f,1 is vertical ) by A24, SPPOL_1:41;
suppose LSeg f,((len f) -' 1) is vertical ; :: thesis: (W-min (L~ f)) `2 < (W-max (L~ f)) `2
then A29: (W-min (L~ f)) `1 = (f /. ((len f) -' 1)) `1 by A19, A15, SPPOL_1:def 3;
then A30: f /. ((len f) -' 1) in W-most (L~ f) by A2, A7, A16, Th16, GOBOARD1:16;
then A31: (f /. ((len f) -' 1)) `2 >= (W-min (L~ f)) `2 by PSCOMP_1:88;
(f /. ((len f) -' 1)) `2 <> (W-min (L~ f)) `2 by A6, A8, A22, A18, A13, A16, A29, GOBOARD7:31, TOPREAL3:11;
then A32: (f /. ((len f) -' 1)) `2 > (W-min (L~ f)) `2 by A31, XXREAL_0:1;
(f /. ((len f) -' 1)) `2 <= (W-max (L~ f)) `2 by A30, PSCOMP_1:88;
hence (W-min (L~ f)) `2 < (W-max (L~ f)) `2 by A32, XXREAL_0:2; :: thesis: verum
end;
end;
end;
hence (W-min (L~ f)) `2 < (W-max (L~ f)) `2 ; :: thesis: verum
end;
suppose that A37: 1 < (W-min (L~ f)) .. f and
A38: (W-min (L~ f)) .. f < len f ; :: thesis: (W-min (L~ f)) `2 < (W-max (L~ f)) `2
A39: (((W-min (L~ f)) .. f) -' 1) + 1 = (W-min (L~ f)) .. f by A37, XREAL_1:237;
then A40: ((W-min (L~ f)) .. f) -' 1 >= 1 by A37, NAT_1:13;
then A41: f /. (((W-min (L~ f)) .. f) -' 1) in LSeg f,(((W-min (L~ f)) .. f) -' 1) by A38, A39, TOPREAL1:27;
((W-min (L~ f)) .. f) -' 1 <= (W-min (L~ f)) .. f by A39, NAT_1:11;
then ((W-min (L~ f)) .. f) -' 1 <= len f by A38, XXREAL_0:2;
then A42: ((W-min (L~ f)) .. f) -' 1 in dom f by A40, FINSEQ_3:27;
then A43: f /. (((W-min (L~ f)) .. f) -' 1) in L~ f by A1, GOBOARD1:16, XXREAL_0:2;
A44: ((W-min (L~ f)) .. f) + 1 <= len f by A38, NAT_1:13;
then A45: f /. (((W-min (L~ f)) .. f) + 1) in LSeg f,((W-min (L~ f)) .. f) by A37, TOPREAL1:27;
((W-min (L~ f)) .. f) + 1 >= 1 by NAT_1:11;
then A46: ((W-min (L~ f)) .. f) + 1 in dom f by A44, FINSEQ_3:27;
then A47: f /. (((W-min (L~ f)) .. f) + 1) in L~ f by A1, GOBOARD1:16, XXREAL_0:2;
A48: W-min (L~ f) <> f /. (((W-min (L~ f)) .. f) + 1) by A3, A6, A46, FINSEQ_4:30, GOBOARD7:31;
A49: W-min (L~ f) in LSeg f,((W-min (L~ f)) .. f) by A6, A37, A44, TOPREAL1:27;
A50: W-min (L~ f) in LSeg f,(((W-min (L~ f)) .. f) -' 1) by A6, A38, A39, A40, TOPREAL1:27;
A51: W-min (L~ f) <> f /. (((W-min (L~ f)) .. f) -' 1) by A4, A6, A39, A42, GOBOARD7:31;
A52: ( not LSeg f,(((W-min (L~ f)) .. f) -' 1) is horizontal or not LSeg f,((W-min (L~ f)) .. f) is horizontal )
proof
assume ( LSeg f,(((W-min (L~ f)) .. f) -' 1) is horizontal & LSeg f,((W-min (L~ f)) .. f) is horizontal ) ; :: thesis: contradiction
then A53: ( (W-min (L~ f)) `2 = (f /. (((W-min (L~ f)) .. f) + 1)) `2 & (W-min (L~ f)) `2 = (f /. (((W-min (L~ f)) .. f) -' 1)) `2 ) by A50, A49, A41, A45, SPPOL_1:def 2;
A54: ( (f /. (((W-min (L~ f)) .. f) + 1)) `1 <= (f /. (((W-min (L~ f)) .. f) -' 1)) `1 or (f /. (((W-min (L~ f)) .. f) + 1)) `1 >= (f /. (((W-min (L~ f)) .. f) -' 1)) `1 ) ;
A55: ( (W-min (L~ f)) `1 <= (f /. (((W-min (L~ f)) .. f) + 1)) `1 & (W-min (L~ f)) `1 <= (f /. (((W-min (L~ f)) .. f) -' 1)) `1 ) by A7, A43, A47, PSCOMP_1:71;
( LSeg f,((W-min (L~ f)) .. f) = LSeg (f /. ((W-min (L~ f)) .. f)),(f /. (((W-min (L~ f)) .. f) + 1)) & LSeg f,(((W-min (L~ f)) .. f) -' 1) = LSeg (f /. ((W-min (L~ f)) .. f)),(f /. (((W-min (L~ f)) .. f) -' 1)) ) by A37, A38, A39, A40, A44, TOPREAL1:def 5;
then ( f /. (((W-min (L~ f)) .. f) -' 1) in LSeg f,((W-min (L~ f)) .. f) or f /. (((W-min (L~ f)) .. f) + 1) in LSeg f,(((W-min (L~ f)) .. f) -' 1) ) by A6, A53, A55, A54, GOBOARD7:9;
then ( f /. (((W-min (L~ f)) .. f) -' 1) in (LSeg f,(((W-min (L~ f)) .. f) -' 1)) /\ (LSeg f,((W-min (L~ f)) .. f)) or f /. (((W-min (L~ f)) .. f) + 1) in (LSeg f,(((W-min (L~ f)) .. f) -' 1)) /\ (LSeg f,((W-min (L~ f)) .. f)) ) by A41, A45, XBOOLE_0:def 4;
then ( ((((W-min (L~ f)) .. f) -' 1) + 1) + 1 = (((W-min (L~ f)) .. f) -' 1) + (1 + 1) & (LSeg f,(((W-min (L~ f)) .. f) -' 1)) /\ (LSeg f,((W-min (L~ f)) .. f)) <> {(f /. ((W-min (L~ f)) .. f))} ) by A6, A51, A48, TARSKI:def 1;
hence contradiction by A39, A40, A44, TOPREAL1:def 8; :: thesis: verum
end;
now
per cases ( LSeg f,(((W-min (L~ f)) .. f) -' 1) is vertical or LSeg f,((W-min (L~ f)) .. f) is vertical ) by A52, SPPOL_1:41;
suppose LSeg f,(((W-min (L~ f)) .. f) -' 1) is vertical ; :: thesis: (W-min (L~ f)) `2 < (W-max (L~ f)) `2
then A56: (W-min (L~ f)) `1 = (f /. (((W-min (L~ f)) .. f) -' 1)) `1 by A50, A41, SPPOL_1:def 3;
then A57: f /. (((W-min (L~ f)) .. f) -' 1) in W-most (L~ f) by A2, A7, A42, Th16, GOBOARD1:16;
then A58: (f /. (((W-min (L~ f)) .. f) -' 1)) `2 >= (W-min (L~ f)) `2 by PSCOMP_1:88;
(f /. (((W-min (L~ f)) .. f) -' 1)) `2 <> (W-min (L~ f)) `2 by A4, A6, A39, A42, A56, GOBOARD7:31, TOPREAL3:11;
then A59: (f /. (((W-min (L~ f)) .. f) -' 1)) `2 > (W-min (L~ f)) `2 by A58, XXREAL_0:1;
(f /. (((W-min (L~ f)) .. f) -' 1)) `2 <= (W-max (L~ f)) `2 by A57, PSCOMP_1:88;
hence (W-min (L~ f)) `2 < (W-max (L~ f)) `2 by A59, XXREAL_0:2; :: thesis: verum
end;
suppose LSeg f,((W-min (L~ f)) .. f) is vertical ; :: thesis: (W-min (L~ f)) `2 < (W-max (L~ f)) `2
then A60: (W-min (L~ f)) `1 = (f /. (((W-min (L~ f)) .. f) + 1)) `1 by A49, A45, SPPOL_1:def 3;
then A61: f /. (((W-min (L~ f)) .. f) + 1) in W-most (L~ f) by A2, A7, A46, Th16, GOBOARD1:16;
then A62: (f /. (((W-min (L~ f)) .. f) + 1)) `2 >= (W-min (L~ f)) `2 by PSCOMP_1:88;
(f /. (((W-min (L~ f)) .. f) + 1)) `2 <> (W-min (L~ f)) `2 by A4, A6, A46, A60, GOBOARD7:31, TOPREAL3:11;
then A63: (f /. (((W-min (L~ f)) .. f) + 1)) `2 > (W-min (L~ f)) `2 by A62, XXREAL_0:1;
(f /. (((W-min (L~ f)) .. f) + 1)) `2 <= (W-max (L~ f)) `2 by A61, PSCOMP_1:88;
hence (W-min (L~ f)) `2 < (W-max (L~ f)) `2 by A63, XXREAL_0:2; :: thesis: verum
end;
end;
end;
hence (W-min (L~ f)) `2 < (W-max (L~ f)) `2 ; :: thesis: verum
end;
end;