let n be Nat; :: thesis: for t being Point of (TUnitSphere n)
for f being Loop of t st n >= 2 & rng f = the carrier of (TUnitSphere n) holds
ex g being Loop of t st
( g,f are_homotopic & rng g <> the carrier of (TUnitSphere n) )

let t be Point of (TUnitSphere n); :: thesis: for f being Loop of t st n >= 2 & rng f = the carrier of (TUnitSphere n) holds
ex g being Loop of t st
( g,f are_homotopic & rng g <> the carrier of (TUnitSphere n) )

let f be Loop of t; :: thesis: ( n >= 2 & rng f = the carrier of (TUnitSphere n) implies ex g being Loop of t st
( g,f are_homotopic & rng g <> the carrier of (TUnitSphere n) ) )

assume that
A1: n >= 2 and
A2: rng f = the carrier of (TUnitSphere n) ; :: thesis: ex g being Loop of t st
( g,f are_homotopic & rng g <> the carrier of (TUnitSphere n) )

reconsider n1 = n + 1 as Element of NAT ;
Tunit_circle n1 is SubSpace of TOP-REAL n1 ;
then A3: TUnitSphere n is SubSpace of TOP-REAL n1 by MFOLD_2:def 4;
[#] (Tunit_circle n1) c= [#] (TOP-REAL n1) by PRE_TOPC:def 4;
then A4: rng f c= the carrier of (TOP-REAL n1) by A2, MFOLD_2:def 4;
dom f = the carrier of I[01] by FUNCT_2:def 1;
then reconsider f1 = f as Function of I[01],(TOP-REAL n1) by A4, FUNCT_2:2;
f1 is continuous by A3, PRE_TOPC:26;
then consider h being FinSequence of REAL such that
A5: ( h . 1 = 0 & h . (len h) = 1 & 5 <= len h & rng h c= the carrier of I[01] & h is increasing & ( for i being Nat
for Q being Subset of I[01]
for W being Subset of (Euclid n1) st 1 <= i & i < len h & Q = [.(h /. i),(h /. (i + 1)).] & W = f1 .: Q holds
diameter W < 1 ) ) by JGRAPH_8:1;
set f2 = f * h;
for x being object st x in rng (f * h) holds
x in the carrier of (TUnitSphere n) ;
then consider x being object such that
A6: ( x in the carrier of (TUnitSphere n) & not x in rng (f * h) ) by A1, TARSKI:2;
A7: [#] (Tunit_circle n1) c= [#] (TOP-REAL n1) by PRE_TOPC:def 4;
A8: x in the carrier of (Tunit_circle n1) by A6, MFOLD_2:def 4;
then reconsider p = x as Point of (TOP-REAL n1) by A7;
p in the carrier of (Tcircle ((0. (TOP-REAL n1)),1)) by A8, TOPREALB:def 7;
then A9: p in Sphere ((0. (TOP-REAL n1)),1) by TOPREALB:9;
then A10: - p in (Sphere ((0. (TOP-REAL n1)),1)) \ {p} by Th3;
then reconsider U = (TOP-REAL n1) | ((Sphere ((0. (TOP-REAL n1)),1)) \ {p}) as non empty SubSpace of TOP-REAL n1 ;
A11: [#] U = (Sphere ((0. (TOP-REAL n1)),1)) \ {p} by PRE_TOPC:def 5;
A12: - p in Sphere ((0. (TOP-REAL n1)),1) by A10, XBOOLE_0:def 5;
then A13: - (- p) in (Sphere ((0. (TOP-REAL n1)),1)) \ {(- p)} by Th3;
then reconsider V = (TOP-REAL n1) | ((Sphere ((0. (TOP-REAL n1)),1)) \ {(- p)}) as non empty SubSpace of TOP-REAL n1 ;
A14: [#] V = (Sphere ((0. (TOP-REAL n1)),1)) \ {(- p)} by PRE_TOPC:def 5;
A15: for i being Element of NAT st 1 <= i & i < len h & not f .: [.(h /. i),(h /. (i + 1)).] c= the carrier of U holds
f .: [.(h /. i),(h /. (i + 1)).] c= the carrier of V
proof
let i be Element of NAT ; :: thesis: ( 1 <= i & i < len h & not f .: [.(h /. i),(h /. (i + 1)).] c= the carrier of U implies f .: [.(h /. i),(h /. (i + 1)).] c= the carrier of V )
assume A16: ( 1 <= i & i < len h ) ; :: thesis: ( f .: [.(h /. i),(h /. (i + 1)).] c= the carrier of U or f .: [.(h /. i),(h /. (i + 1)).] c= the carrier of V )
i in Seg (len h) by A16, FINSEQ_1:1;
then A17: i in dom h by FINSEQ_1:def 3;
reconsider h1 = h as real-valued FinSequence ;
reconsider i1 = i + 1 as Nat ;
A18: ( i1 <= len h & 1 <= i1 ) by A16, NAT_1:13;
then i1 in Seg (len h) by FINSEQ_1:1;
then A19: i1 in dom h by FINSEQ_1:def 3;
h1 . (i + 1) <= 1 by A5, A18, EUCLID_7:7;
then A20: h /. (i + 1) <= 1 by A19, PARTFUN1:def 6;
h1 . 1 <= h1 . i by A5, A16, EUCLID_7:7;
then 0 <= h /. i by A5, A17, PARTFUN1:def 6;
then reconsider Q = [.(h /. i),(h /. (i + 1)).] as Subset of I[01] by A20, BORSUK_1:40, XXREAL_1:34;
f .: Q c= the carrier of (TUnitSphere n) ;
then f .: Q c= [#] (Tunit_circle n1) by MFOLD_2:def 4;
then f .: Q c= the carrier of (Tcircle ((0. (TOP-REAL n1)),1)) by TOPREALB:def 7;
then A21: f .: Q c= Sphere ((0. (TOP-REAL n1)),1) by TOPREALB:9;
reconsider W = f1 .: Q as Subset of (Euclid n1) by EUCLID:67;
A22: diameter W < 1 by A16, A5;
Sphere ((0. (TOP-REAL n1)),1) is bounded Subset of (Euclid n1) by JORDAN2C:11;
then A23: W is bounded by A21, TBSP_1:14;
( not p in f .: Q or not - p in f .: Q )
proof
assume A24: ( p in f .: Q & - p in f .: Q ) ; :: thesis: contradiction
reconsider p1 = p, p2 = - p as Point of (Euclid n1) by EUCLID:67;
A25: dist (p1,p2) <= diameter W by A24, A23, TBSP_1:def 8;
A26: Euclid n1 = MetrStruct(# (REAL n1),(Pitag_dist n1) #) by EUCLID:def 7;
reconsider p3 = p1, p4 = p2 as Element of REAL n1 by A26;
reconsider r1 = 1 as Real ;
dist (p1,p2) = the distance of (Euclid n1) . (p1,p2) by METRIC_1:def 1
.= |.(p3 - p4).| by A26, EUCLID:def 6 ;
then |.(p - (- p)).| < 1 by A25, A22, XXREAL_0:2;
then |.(p + (- (- p))).| < 1 ;
then |.((r1 * p) + p).| < 1 by RLVECT_1:def 8;
then |.((r1 * p) + (r1 * p)).| < 1 by RLVECT_1:def 8;
then |.((1 + 1) * p).| < 1 by RLVECT_1:def 6;
then A27: |.2.| * |.p.| < 1 by EUCLID:11;
|.(p - (0. (TOP-REAL n1))).| = 1 by A9, TOPREAL9:9;
then |.(p + (- (0. (TOP-REAL n1)))).| = 1 ;
then |.(p + ((- 1) * (0. (TOP-REAL n1)))).| = 1 by RLVECT_1:16;
then |.(p + (0. (TOP-REAL n1))).| = 1 by RLVECT_1:10;
then A28: |.p.| = 1 by RLVECT_1:4;
|.2.| = 2 by COMPLEX1:43;
hence contradiction by A28, A27; :: thesis: verum
end;
hence ( f .: [.(h /. i),(h /. (i + 1)).] c= the carrier of U or f .: [.(h /. i),(h /. (i + 1)).] c= the carrier of V ) by A14, A11, A21, ZFMISC_1:34; :: thesis: verum
end;
( f is Path of t,t & t,t are_connected ) ;
then reconsider c = f as with_endpoints Curve of (TUnitSphere n) by Th25;
A29: 2 <= len h by A5, XXREAL_0:2;
A30: ( inf (dom f) = 0 & sup (dom f) = 1 ) by Th4;
then consider fc1 being FinSequence of Curves (TUnitSphere n) such that
A31: ( len fc1 = (len h) - 1 & c = Sum fc1 & ( for i being Nat st 1 <= i & i <= len fc1 holds
fc1 /. i = c | [.(h /. i),(h /. (i + 1)).] ) ) by A5, A29, Th45;
A32: for i being Nat st 1 <= i & i <= len fc1 & not rng (fc1 /. i) c= the carrier of U holds
rng (fc1 /. i) c= the carrier of V
proof
let i be Nat; :: thesis: ( 1 <= i & i <= len fc1 & not rng (fc1 /. i) c= the carrier of U implies rng (fc1 /. i) c= the carrier of V )
assume A33: ( 1 <= i & i <= len fc1 ) ; :: thesis: ( rng (fc1 /. i) c= the carrier of U or rng (fc1 /. i) c= the carrier of V )
then A34: i < ((len h) - 1) + 1 by A31, NAT_1:13;
reconsider i0 = i as Element of NAT by ORDINAL1:def 12;
f .: [.(h /. i0),(h /. (i0 + 1)).] = rng (f | [.(h /. i0),(h /. (i0 + 1)).]) by RELAT_1:115
.= rng (fc1 /. i) by A33, A31 ;
hence ( rng (fc1 /. i) c= the carrier of U or rng (fc1 /. i) c= the carrier of V ) by A33, A34, A15; :: thesis: verum
end;
A35: for c1 being with_endpoints Curve of (TUnitSphere n) st rng c1 c= the carrier of V & the_first_point_of c1 <> p & the_last_point_of c1 <> p & not inf (dom c1) = sup (dom c1) holds
ex c2 being with_endpoints Curve of (TUnitSphere n) st
( c1,c2 are_homotopic & rng c2 c= the carrier of U & dom c1 = dom c2 )
proof
let c1 be with_endpoints Curve of (TUnitSphere n); :: thesis: ( rng c1 c= the carrier of V & the_first_point_of c1 <> p & the_last_point_of c1 <> p & not inf (dom c1) = sup (dom c1) implies ex c2 being with_endpoints Curve of (TUnitSphere n) st
( c1,c2 are_homotopic & rng c2 c= the carrier of U & dom c1 = dom c2 ) )

assume A36: rng c1 c= the carrier of V ; :: thesis: ( not the_first_point_of c1 <> p or not the_last_point_of c1 <> p or inf (dom c1) = sup (dom c1) or ex c2 being with_endpoints Curve of (TUnitSphere n) st
( c1,c2 are_homotopic & rng c2 c= the carrier of U & dom c1 = dom c2 ) )

assume A37: ( the_first_point_of c1 <> p & the_last_point_of c1 <> p ) ; :: thesis: ( inf (dom c1) = sup (dom c1) or ex c2 being with_endpoints Curve of (TUnitSphere n) st
( c1,c2 are_homotopic & rng c2 c= the carrier of U & dom c1 = dom c2 ) )

assume A38: not inf (dom c1) = sup (dom c1) ; :: thesis: ex c2 being with_endpoints Curve of (TUnitSphere n) st
( c1,c2 are_homotopic & rng c2 c= the carrier of U & dom c1 = dom c2 )

set t1 = the_first_point_of c1;
set t2 = the_last_point_of c1;
reconsider p1 = c1 * (L[01] (0,1,(inf (dom c1)),(sup (dom c1)))) as Path of the_first_point_of c1, the_last_point_of c1 by Th29;
stereographic_projection (V,(- p)) is being_homeomorphism by A12, A14, MFOLD_2:31;
then A39: TPlane ((- p),(0. (TOP-REAL n1))),V are_homeomorphic by T_0TOPSP:def 1;
- p <> 0. (TOP-REAL n1)
proof
assume - p = 0. (TOP-REAL n1) ; :: thesis: contradiction
then (- p) - (0. (TOP-REAL n1)) = 0. (TOP-REAL n1) by RLVECT_1:5;
then |.(0. (TOP-REAL n1)).| = 1 by A12, TOPREAL9:9;
hence contradiction by EUCLID_2:39; :: thesis: verum
end;
then A40: TOP-REAL n, TPlane ((- p),(0. (TOP-REAL n1))) are_homeomorphic by MFOLD_2:29;
then TOP-REAL n,V are_homeomorphic by A39, BORSUK_3:3;
then consider fh being Function of (TOP-REAL n),V such that
A41: fh is being_homeomorphism ;
A42: ( dom fh = [#] (TOP-REAL n) & rng fh = [#] V ) by A41, TOPS_2:58;
A43: [#] V is infinite by A1, A41, A42, CARD_1:59;
reconsider v = p as Point of V by A13, A14;
reconsider S = ([#] V) \ {v} as non empty Subset of V by A43, RAMSEY_1:4;
A44: V | S is pathwise_connected by A1, A40, Th10, A39, BORSUK_3:3;
A45: the_first_point_of c1 in rng c1 by Th31;
A46: not the_first_point_of c1 in {v} by A37, TARSKI:def 1;
A47: the_last_point_of c1 in rng c1 by Th31;
A48: not the_last_point_of c1 in {v} by A37, TARSKI:def 1;
( the_first_point_of c1 in S & the_last_point_of c1 in S ) by A45, A46, A47, A36, A48, XBOOLE_0:def 5;
then ( the_first_point_of c1 in [#] (V | S) & the_last_point_of c1 in [#] (V | S) ) by PRE_TOPC:def 5;
then reconsider v1 = the_first_point_of c1, v2 = the_last_point_of c1 as Point of (V | S) ;
A49: v1,v2 are_connected by A44;
then consider p3 being Function of I[01],(V | S) such that
A50: ( p3 is continuous & p3 . 0 = v1 & p3 . 1 = v2 ) ;
reconsider p3 = p3 as Path of v1,v2 by A50, A49, BORSUK_2:def 2;
A51: Tcircle ((0. (TOP-REAL n1)),1) = Tunit_circle n1 by TOPREALB:def 7
.= TUnitSphere n by MFOLD_2:def 4 ;
A52: V is SubSpace of (TOP-REAL n1) | (Sphere ((0. (TOP-REAL n1)),1)) by TOPMETR:22, XBOOLE_1:36;
then A53: V is SubSpace of Tcircle ((0. (TOP-REAL n1)),1) by TOPREALB:def 6;
reconsider S0 = V as non empty SubSpace of TUnitSphere n by A51, A52, TOPREALB:def 6;
reconsider s1 = the_first_point_of c1, s2 = the_last_point_of c1 as Point of S0 by A45, A47, A36;
A54: dom p3 = [#] I[01] by FUNCT_2:def 1;
A55: [#] S0 c= [#] (TUnitSphere n) by PRE_TOPC:def 4;
rng p3 c= [#] (V | S) ;
then A56: rng p3 c= S by PRE_TOPC:def 5;
then rng p3 c= [#] S0 by XBOOLE_1:1;
then reconsider p3 = p3 as Function of I[01],(TUnitSphere n) by A54, A55, FUNCT_2:2, XBOOLE_1:1;
V | S is SubSpace of TUnitSphere n by A53, A51, TSEP_1:7;
then A57: p3 is continuous by A50, PRE_TOPC:26;
then A58: the_first_point_of c1, the_last_point_of c1 are_connected by A50;
then reconsider p2 = p3 as Path of the_first_point_of c1, the_last_point_of c1 by A50, A57, BORSUK_2:def 2;
rng p1 c= rng c1 by RELAT_1:26;
then A59: rng p1 c= [#] V by A36;
A60: rng p2 c= [#] V by A56, XBOOLE_1:1;
A61: s1,s2 are_connected by A58, A60, JORDAN:29;
reconsider p5 = p1, p6 = p2 as Path of s1,s2 by A58, A60, A59, JORDAN:29;
reconsider n0 = n as Element of NAT by ORDINAL1:def 12;
S0 is simply_connected by Th14, A39;
then Class ((EqRel (S0,s1,s2)),p5) = Class ((EqRel (S0,s1,s2)),p6) by Th12;
then p5,p6 are_homotopic by A61, TOPALG_1:46;
then A62: p1,p2 are_homotopic by A58, A61, Th6;
set r1 = inf (dom c1);
set r2 = sup (dom c1);
A63: inf (dom c1) <= sup (dom c1) by XXREAL_2:40;
then A64: inf (dom c1) < sup (dom c1) by A38, XXREAL_0:1;
then reconsider c2 = p2 * (L[01] ((inf (dom c1)),(sup (dom c1)),0,1)) as with_endpoints Curve of (TUnitSphere n) by A58, Th32;
take c2 ; :: thesis: ( c1,c2 are_homotopic & rng c2 c= the carrier of U & dom c1 = dom c2 )
rng (L[01] ((inf (dom c1)),(sup (dom c1)),0,1)) c= [#] (Closed-Interval-TSpace (0,1)) by RELAT_1:def 19;
then rng (L[01] ((inf (dom c1)),(sup (dom c1)),0,1)) c= dom p2 by FUNCT_2:def 1, TOPMETR:20;
then dom c2 = dom (L[01] ((inf (dom c1)),(sup (dom c1)),0,1)) by RELAT_1:27;
then dom c2 = [#] (Closed-Interval-TSpace ((inf (dom c1)),(sup (dom c1)))) by FUNCT_2:def 1;
then A65: dom c2 = [.(inf (dom c1)),(sup (dom c1)).] by A63, TOPMETR:18;
A66: c2 * (L[01] (0,1,(inf (dom c1)),(sup (dom c1)))) = p2 * ((L[01] ((inf (dom c1)),(sup (dom c1)),0,1)) * (L[01] (0,1,(inf (dom c1)),(sup (dom c1))))) by RELAT_1:36
.= p2 * (id (Closed-Interval-TSpace (0,1))) by Th1, A64, Th2
.= p2 by FUNCT_2:17, TOPMETR:20 ;
( inf (dom c1) = inf (dom c2) & sup (dom c1) = sup (dom c2) ) by A65, Th27;
hence c1,c2 are_homotopic by A62, A66; :: thesis: ( rng c2 c= the carrier of U & dom c1 = dom c2 )
A67: rng c2 c= rng p2 by RELAT_1:26;
A68: ((Sphere ((0. (TOP-REAL n1)),1)) \ {p}) \ {(- p)} c= (Sphere ((0. (TOP-REAL n1)),1)) \ {p} by XBOOLE_1:36;
rng c2 c= ([#] V) \ {p} by A56, A67;
then rng c2 c= (Sphere ((0. (TOP-REAL n1)),1)) \ ({(- p)} \/ {p}) by A14, XBOOLE_1:41;
then rng c2 c= ((Sphere ((0. (TOP-REAL n1)),1)) \ {p}) \ {(- p)} by XBOOLE_1:41;
hence rng c2 c= the carrier of U by A11, A68; :: thesis: dom c1 = dom c2
thus dom c1 = dom c2 by A65, Th27; :: thesis: verum
end;
A69: for i being Nat st 1 <= i & i <= len fc1 holds
( i + 1 in dom h & i in dom h & dom (fc1 /. i) = [.(h /. i),(h /. (i + 1)).] & h /. i < h /. (i + 1) )
proof
let i be Nat; :: thesis: ( 1 <= i & i <= len fc1 implies ( i + 1 in dom h & i in dom h & dom (fc1 /. i) = [.(h /. i),(h /. (i + 1)).] & h /. i < h /. (i + 1) ) )
assume A70: ( 1 <= i & i <= len fc1 ) ; :: thesis: ( i + 1 in dom h & i in dom h & dom (fc1 /. i) = [.(h /. i),(h /. (i + 1)).] & h /. i < h /. (i + 1) )
A71: 1 <= 1 + i by NAT_1:11;
A72: i + 1 <= ((len h) - 1) + 1 by A70, A31, XREAL_1:6;
then i + 1 in Seg (len h) by A71, FINSEQ_1:1;
hence A73: i + 1 in dom h by FINSEQ_1:def 3; :: thesis: ( i in dom h & dom (fc1 /. i) = [.(h /. i),(h /. (i + 1)).] & h /. i < h /. (i + 1) )
A74: i < i + 1 by NAT_1:13;
i <= len h by A72, NAT_1:13;
then i in Seg (len h) by A70, FINSEQ_1:1;
hence A75: i in dom h by FINSEQ_1:def 3; :: thesis: ( dom (fc1 /. i) = [.(h /. i),(h /. (i + 1)).] & h /. i < h /. (i + 1) )
A76: h /. i = h . i by A75, PARTFUN1:def 6;
A77: h /. (i + 1) = h . (i + 1) by A73, PARTFUN1:def 6;
A78: 0 <= h . i
proof end;
A80: h . (i + 1) <= 1
proof
per cases ( i + 1 = len h or not i + 1 = len h ) ;
end;
end;
[.(h . i),(h . (i + 1)).] c= [.0,1.] by A78, A80, XXREAL_1:34;
then A83: [.(h . i),(h . (i + 1)).] c= dom c by A30, Th27;
A84: fc1 /. i = c | [.(h /. i),(h /. (i + 1)).] by A31, A70;
thus dom (fc1 /. i) = [.(h /. i),(h /. (i + 1)).] by A84, A83, A76, A77, RELAT_1:62; :: thesis: h /. i < h /. (i + 1)
thus h /. i < h /. (i + 1) by A77, A76, A75, A73, A74, A5, VALUED_0:def 13; :: thesis: verum
end;
A85: for i being Nat st 1 <= i & i <= len fc1 holds
( fc1 /. i is with_endpoints & ( for c1 being with_endpoints Curve of (TUnitSphere n) st c1 = fc1 /. i holds
ex c2 being with_endpoints Curve of (TUnitSphere n) st
( c1,c2 are_homotopic & rng c2 c= the carrier of U & dom c1 = dom c2 & dom c1 = [.(h /. i),(h /. (i + 1)).] ) ) )
proof
let i be Nat; :: thesis: ( 1 <= i & i <= len fc1 implies ( fc1 /. i is with_endpoints & ( for c1 being with_endpoints Curve of (TUnitSphere n) st c1 = fc1 /. i holds
ex c2 being with_endpoints Curve of (TUnitSphere n) st
( c1,c2 are_homotopic & rng c2 c= the carrier of U & dom c1 = dom c2 & dom c1 = [.(h /. i),(h /. (i + 1)).] ) ) ) )

assume A86: ( 1 <= i & i <= len fc1 ) ; :: thesis: ( fc1 /. i is with_endpoints & ( for c1 being with_endpoints Curve of (TUnitSphere n) st c1 = fc1 /. i holds
ex c2 being with_endpoints Curve of (TUnitSphere n) st
( c1,c2 are_homotopic & rng c2 c= the carrier of U & dom c1 = dom c2 & dom c1 = [.(h /. i),(h /. (i + 1)).] ) ) )

A87: fc1 /. i = c | [.(h /. i),(h /. (i + 1)).] by A31, A86;
A88: i + 1 in dom h by A69, A86;
A89: i in dom h by A69, A86;
A90: i < i + 1 by NAT_1:13;
A91: h . i < h . (i + 1) by A89, A88, A90, A5, VALUED_0:def 13;
A92: dom (fc1 /. i) = [.(h /. i),(h /. (i + 1)).] by A69, A86;
h /. i < h /. (i + 1) by A69, A86;
then ( dom (fc1 /. i) is left_end & dom (fc1 /. i) is right_end ) by A92, XXREAL_2:33;
then ( fc1 /. i is with_first_point & fc1 /. i is with_last_point ) ;
hence fc1 /. i is with_endpoints ; :: thesis: for c1 being with_endpoints Curve of (TUnitSphere n) st c1 = fc1 /. i holds
ex c2 being with_endpoints Curve of (TUnitSphere n) st
( c1,c2 are_homotopic & rng c2 c= the carrier of U & dom c1 = dom c2 & dom c1 = [.(h /. i),(h /. (i + 1)).] )

let c1 be with_endpoints Curve of (TUnitSphere n); :: thesis: ( c1 = fc1 /. i implies ex c2 being with_endpoints Curve of (TUnitSphere n) st
( c1,c2 are_homotopic & rng c2 c= the carrier of U & dom c1 = dom c2 & dom c1 = [.(h /. i),(h /. (i + 1)).] ) )

assume A93: c1 = fc1 /. i ; :: thesis: ex c2 being with_endpoints Curve of (TUnitSphere n) st
( c1,c2 are_homotopic & rng c2 c= the carrier of U & dom c1 = dom c2 & dom c1 = [.(h /. i),(h /. (i + 1)).] )

A94: dom c1 = [.(inf (dom c1)),(sup (dom c1)).] by Th27;
A95: inf (dom c1) <= sup (dom c1) by XXREAL_2:40;
A96: inf (dom c1) = h /. i by A93, A94, A95, A92, XXREAL_1:66;
A97: h /. i = h . i by A89, PARTFUN1:def 6;
A98: sup (dom c1) = h /. (i + 1) by A93, A94, A95, A92, XXREAL_1:66;
A99: h /. (i + 1) = h . (i + 1) by A88, PARTFUN1:def 6;
per cases ( rng c1 c= the carrier of U or rng c1 c= the carrier of V ) by A32, A86, A93;
suppose A100: rng c1 c= the carrier of U ; :: thesis: ex c2 being with_endpoints Curve of (TUnitSphere n) st
( c1,c2 are_homotopic & rng c2 c= the carrier of U & dom c1 = dom c2 & dom c1 = [.(h /. i),(h /. (i + 1)).] )

take c1 ; :: thesis: ( c1,c1 are_homotopic & rng c1 c= the carrier of U & dom c1 = dom c1 & dom c1 = [.(h /. i),(h /. (i + 1)).] )
thus ( c1,c1 are_homotopic & rng c1 c= the carrier of U & dom c1 = dom c1 & dom c1 = [.(h /. i),(h /. (i + 1)).] ) by A100, A93, A69, A86; :: thesis: verum
end;
suppose A101: rng c1 c= the carrier of V ; :: thesis: ex c2 being with_endpoints Curve of (TUnitSphere n) st
( c1,c2 are_homotopic & rng c2 c= the carrier of U & dom c1 = dom c2 & dom c1 = [.(h /. i),(h /. (i + 1)).] )

A102: rng h c= dom f by A5, FUNCT_2:def 1;
then A103: dom (f * h) = dom h by RELAT_1:27;
A104: i + 1 in dom (f * h) by A102, A88, RELAT_1:27;
A105: the_first_point_of c1 <> p
proof
assume A106: the_first_point_of c1 = p ; :: thesis: contradiction
inf (dom c1) in dom c1 by A94, A95, XXREAL_1:1;
then c1 . (inf (dom c1)) = f . (h . i) by A96, A97, A93, A87, FUNCT_1:47
.= (f * h) . i by A103, A89, FUNCT_1:12 ;
hence contradiction by A6, A106, A103, A89, FUNCT_1:3; :: thesis: verum
end;
A107: the_last_point_of c1 <> p
proof
assume A108: the_last_point_of c1 = p ; :: thesis: contradiction
sup (dom c1) in dom c1 by A94, A95, XXREAL_1:1;
then c1 . (sup (dom c1)) = f . (h . (i + 1)) by A98, A99, A93, A87, FUNCT_1:47
.= (f * h) . (i + 1) by A104, FUNCT_1:12 ;
hence contradiction by A6, A108, A104, FUNCT_1:3; :: thesis: verum
end;
consider c2 being with_endpoints Curve of (TUnitSphere n) such that
A109: ( c1,c2 are_homotopic & rng c2 c= the carrier of U & dom c1 = dom c2 ) by A35, A101, A105, A107, A96, A98, A91, A97, A99;
take c2 ; :: thesis: ( c1,c2 are_homotopic & rng c2 c= the carrier of U & dom c1 = dom c2 & dom c1 = [.(h /. i),(h /. (i + 1)).] )
thus ( c1,c2 are_homotopic & rng c2 c= the carrier of U & dom c1 = dom c2 & dom c1 = [.(h /. i),(h /. (i + 1)).] ) by A109, A93, A69, A86; :: thesis: verum
end;
end;
end;
defpred S1[ set , set ] means for i being Nat
for c1 being with_endpoints Curve of (TUnitSphere n) st i = $1 & c1 = fc1 /. i holds
ex c2 being with_endpoints Curve of (TUnitSphere n) st
( c2 = $2 & c2,c1 are_homotopic & rng c2 c= the carrier of U & dom c1 = dom c2 & dom c1 = [.(h /. i),(h /. (i + 1)).] );
A110: for k being Nat st k in Seg (len fc1) holds
ex x being Element of Curves (TUnitSphere n) st S1[k,x]
proof
let k be Nat; :: thesis: ( k in Seg (len fc1) implies ex x being Element of Curves (TUnitSphere n) st S1[k,x] )
assume k in Seg (len fc1) ; :: thesis: ex x being Element of Curves (TUnitSphere n) st S1[k,x]
then A111: ( 1 <= k & k <= len fc1 ) by FINSEQ_1:1;
set c1 = fc1 /. k;
reconsider c1 = fc1 /. k as with_endpoints Curve of (TUnitSphere n) by A111, A85;
consider c2 being with_endpoints Curve of (TUnitSphere n) such that
A112: ( c1,c2 are_homotopic & rng c2 c= the carrier of U & dom c1 = dom c2 & dom c1 = [.(h /. k),(h /. (k + 1)).] ) by A85, A111;
reconsider x = c2 as Element of Curves (TUnitSphere n) ;
take x ; :: thesis: S1[k,x]
thus S1[k,x] by A112; :: thesis: verum
end;
ex p being FinSequence of Curves (TUnitSphere n) st
( dom p = Seg (len fc1) & ( for k being Nat st k in Seg (len fc1) holds
S1[k,p . k] ) ) from FINSEQ_1:sch 5(A110);
then consider fc2 being FinSequence of Curves (TUnitSphere n) such that
A113: ( dom fc2 = Seg (len fc1) & ( for k being Nat st k in Seg (len fc1) holds
S1[k,fc2 . k] ) ) ;
A114: len fc2 = len fc1 by A113, FINSEQ_1:def 3;
A115: 2 - 1 <= (len h) - 1 by A29, XREAL_1:9;
then A116: len fc2 > 0 by A31, A113, FINSEQ_1:def 3;
A117: for i being Nat st 1 <= i & i < len fc2 holds
( (fc2 /. i) . (sup (dom (fc2 /. i))) = (fc2 /. (i + 1)) . (inf (dom (fc2 /. (i + 1)))) & sup (dom (fc2 /. i)) = inf (dom (fc2 /. (i + 1))) )
proof
let i be Nat; :: thesis: ( 1 <= i & i < len fc2 implies ( (fc2 /. i) . (sup (dom (fc2 /. i))) = (fc2 /. (i + 1)) . (inf (dom (fc2 /. (i + 1)))) & sup (dom (fc2 /. i)) = inf (dom (fc2 /. (i + 1))) ) )
assume A118: ( 1 <= i & i < len fc2 ) ; :: thesis: ( (fc2 /. i) . (sup (dom (fc2 /. i))) = (fc2 /. (i + 1)) . (inf (dom (fc2 /. (i + 1)))) & sup (dom (fc2 /. i)) = inf (dom (fc2 /. (i + 1))) )
then ( 1 <= i & i <= len fc1 ) by A113, FINSEQ_1:def 3;
then A119: i in Seg (len fc1) by FINSEQ_1:1;
set ci = fc1 /. i;
reconsider ci = fc1 /. i as with_endpoints Curve of (TUnitSphere n) by A118, A114, A85;
consider di being with_endpoints Curve of (TUnitSphere n) such that
A120: ( di = fc2 . i & di,ci are_homotopic & rng di c= the carrier of U & dom ci = dom di & dom ci = [.(h /. i),(h /. (i + 1)).] ) by A119, A113;
1 + 1 <= i + 1 by A118, XREAL_1:6;
then A121: 1 <= i + 1 by XXREAL_0:2;
A122: i + 1 <= len fc2 by A118, NAT_1:13;
then A123: i + 1 in Seg (len fc1) by A114, A121, FINSEQ_1:1;
set ci1 = fc1 /. (i + 1);
reconsider ci1 = fc1 /. (i + 1) as with_endpoints Curve of (TUnitSphere n) by A121, A122, A114, A85;
consider di1 being with_endpoints Curve of (TUnitSphere n) such that
A124: ( di1 = fc2 . (i + 1) & di1,ci1 are_homotopic & rng di1 c= the carrier of U & dom ci1 = dom di1 & dom ci1 = [.(h /. (i + 1)),(h /. ((i + 1) + 1)).] ) by A123, A113;
A125: i + 1 in dom fc2 by A122, A113, A114, A121, FINSEQ_1:1;
A126: h /. i < h /. (i + 1) by A69, A118, A114;
A127: h /. (i + 1) < h /. ((i + 1) + 1) by A69, A121, A122, A114;
A128: dom (fc1 /. i) = [.(h /. i),(h /. (i + 1)).] by A69, A118, A114;
A129: dom (fc1 /. (i + 1)) = [.(h /. (i + 1)),(h /. ((i + 1) + 1)).] by A69, A121, A122, A114;
A130: h /. (i + 1) in [.(h /. i),(h /. (i + 1)).] by A126, XXREAL_1:1;
A131: h /. (i + 1) in [.(h /. (i + 1)),(h /. ((i + 1) + 1)).] by A127, XXREAL_1:1;
A132: fc2 /. i = fc2 . i by A119, A113, PARTFUN1:def 6;
A133: fc2 /. (i + 1) = fc2 . (i + 1) by A125, PARTFUN1:def 6;
thus (fc2 /. i) . (sup (dom (fc2 /. i))) = the_last_point_of di by A120, A132
.= the_last_point_of ci by A120, Th35
.= (fc1 /. i) . (h /. (i + 1)) by A126, A128, XXREAL_2:29
.= (c | [.(h /. i),(h /. (i + 1)).]) . (h /. (i + 1)) by A31, A118, A114
.= c . (h /. (i + 1)) by A130, FUNCT_1:49
.= (c | [.(h /. (i + 1)),(h /. ((i + 1) + 1)).]) . (h /. (i + 1)) by A131, FUNCT_1:49
.= (fc1 /. (i + 1)) . (h /. (i + 1)) by A31, A121, A122, A114
.= the_first_point_of ci1 by A127, A129, XXREAL_2:25
.= the_first_point_of di1 by A124, Th35
.= (fc2 /. (i + 1)) . (inf (dom (fc2 /. (i + 1)))) by A124, A133 ; :: thesis: sup (dom (fc2 /. i)) = inf (dom (fc2 /. (i + 1)))
A134: dom (fc2 /. i) = [.(h /. i),(h /. (i + 1)).] by A120, A119, A113, PARTFUN1:def 6;
A135: dom (fc2 /. (i + 1)) = [.(h /. (i + 1)),(h /. (i + 2)).] by A124, A125, PARTFUN1:def 6;
thus sup (dom (fc2 /. i)) = h /. (i + 1) by A134, A126, XXREAL_2:29
.= inf (dom (fc2 /. (i + 1))) by A135, A127, XXREAL_2:25 ; :: thesis: verum
end;
A136: for i being Nat st 1 <= i & i <= len fc2 holds
fc2 /. i is with_endpoints
proof
let i be Nat; :: thesis: ( 1 <= i & i <= len fc2 implies fc2 /. i is with_endpoints )
assume A137: ( 1 <= i & i <= len fc2 ) ; :: thesis: fc2 /. i is with_endpoints
then A138: i in Seg (len fc1) by A114, FINSEQ_1:1;
set ci = fc1 /. i;
reconsider ci = fc1 /. i as with_endpoints Curve of (TUnitSphere n) by A137, A114, A85;
consider di being with_endpoints Curve of (TUnitSphere n) such that
A139: ( di = fc2 . i & di,ci are_homotopic & rng di c= the carrier of U & dom ci = dom di & dom ci = [.(h /. i),(h /. (i + 1)).] ) by A138, A113;
thus fc2 /. i is with_endpoints by A139, A138, A113, PARTFUN1:def 6; :: thesis: verum
end;
consider c0 being with_endpoints Curve of (TUnitSphere n) such that
A140: ( Sum fc2 = c0 & dom c0 = [.(inf (dom (fc2 /. 1))),(sup (dom (fc2 /. (len fc2)))).] & the_first_point_of c0 = (fc2 /. 1) . (inf (dom (fc2 /. 1))) & the_last_point_of c0 = (fc2 /. (len fc2)) . (sup (dom (fc2 /. (len fc2)))) ) by A117, A136, A116, Th43;
A141: for i being Nat st 1 <= i & i < len fc1 holds
( (fc1 /. i) . (sup (dom (fc1 /. i))) = (fc1 /. (i + 1)) . (inf (dom (fc1 /. (i + 1)))) & sup (dom (fc1 /. i)) = inf (dom (fc1 /. (i + 1))) )
proof
let i be Nat; :: thesis: ( 1 <= i & i < len fc1 implies ( (fc1 /. i) . (sup (dom (fc1 /. i))) = (fc1 /. (i + 1)) . (inf (dom (fc1 /. (i + 1)))) & sup (dom (fc1 /. i)) = inf (dom (fc1 /. (i + 1))) ) )
assume A142: ( 1 <= i & i < len fc1 ) ; :: thesis: ( (fc1 /. i) . (sup (dom (fc1 /. i))) = (fc1 /. (i + 1)) . (inf (dom (fc1 /. (i + 1)))) & sup (dom (fc1 /. i)) = inf (dom (fc1 /. (i + 1))) )
A143: i in Seg (len fc1) by A142, FINSEQ_1:1;
set ci = fc1 /. i;
reconsider ci = fc1 /. i as with_endpoints Curve of (TUnitSphere n) by A142, A85;
consider di being with_endpoints Curve of (TUnitSphere n) such that
A144: ( di = fc2 . i & di,ci are_homotopic & rng di c= the carrier of U & dom ci = dom di & dom ci = [.(h /. i),(h /. (i + 1)).] ) by A143, A113;
1 + 1 <= i + 1 by A142, XREAL_1:6;
then A145: 1 <= i + 1 by XXREAL_0:2;
A146: i + 1 <= len fc2 by A114, A142, NAT_1:13;
then A147: i + 1 in Seg (len fc1) by A114, A145, FINSEQ_1:1;
set ci1 = fc1 /. (i + 1);
reconsider ci1 = fc1 /. (i + 1) as with_endpoints Curve of (TUnitSphere n) by A145, A146, A114, A85;
consider di1 being with_endpoints Curve of (TUnitSphere n) such that
A148: ( di1 = fc2 . (i + 1) & di1,ci1 are_homotopic & rng di1 c= the carrier of U & dom ci1 = dom di1 & dom ci1 = [.(h /. (i + 1)),(h /. ((i + 1) + 1)).] ) by A147, A113;
A149: h /. i < h /. (i + 1) by A69, A142;
A150: h /. (i + 1) < h /. ((i + 1) + 1) by A69, A145, A146, A114;
A151: dom (fc1 /. i) = [.(h /. i),(h /. (i + 1)).] by A69, A142;
A152: dom (fc1 /. (i + 1)) = [.(h /. (i + 1)),(h /. ((i + 1) + 1)).] by A69, A145, A146, A114;
A153: h /. (i + 1) in [.(h /. i),(h /. (i + 1)).] by A149, XXREAL_1:1;
A154: h /. (i + 1) in [.(h /. (i + 1)),(h /. ((i + 1) + 1)).] by A150, XXREAL_1:1;
thus (fc1 /. i) . (sup (dom (fc1 /. i))) = (fc1 /. i) . (h /. (i + 1)) by A149, A151, XXREAL_2:29
.= (c | [.(h /. i),(h /. (i + 1)).]) . (h /. (i + 1)) by A31, A142
.= c . (h /. (i + 1)) by A153, FUNCT_1:49
.= (c | [.(h /. (i + 1)),(h /. ((i + 1) + 1)).]) . (h /. (i + 1)) by A154, FUNCT_1:49
.= (fc1 /. (i + 1)) . (h /. (i + 1)) by A31, A145, A146, A114
.= (fc1 /. (i + 1)) . (inf (dom (fc1 /. (i + 1)))) by A150, A152, XXREAL_2:25 ; :: thesis: sup (dom (fc1 /. i)) = inf (dom (fc1 /. (i + 1)))
thus sup (dom (fc1 /. i)) = h /. (i + 1) by A144, A149, XXREAL_2:29
.= inf (dom (fc1 /. (i + 1))) by A148, A150, XXREAL_2:25 ; :: thesis: verum
end;
for i being Nat st 1 <= i & i <= len fc2 holds
ex c3, c4 being with_endpoints Curve of (TUnitSphere n) st
( c3 = fc2 /. i & c4 = fc1 /. i & c3,c4 are_homotopic & dom c3 = dom c4 )
proof
let i be Nat; :: thesis: ( 1 <= i & i <= len fc2 implies ex c3, c4 being with_endpoints Curve of (TUnitSphere n) st
( c3 = fc2 /. i & c4 = fc1 /. i & c3,c4 are_homotopic & dom c3 = dom c4 ) )

assume A155: ( 1 <= i & i <= len fc2 ) ; :: thesis: ex c3, c4 being with_endpoints Curve of (TUnitSphere n) st
( c3 = fc2 /. i & c4 = fc1 /. i & c3,c4 are_homotopic & dom c3 = dom c4 )

then A156: i in Seg (len fc1) by A114, FINSEQ_1:1;
set ci = fc1 /. i;
reconsider ci = fc1 /. i as with_endpoints Curve of (TUnitSphere n) by A155, A114, A85;
consider di being with_endpoints Curve of (TUnitSphere n) such that
A157: ( di = fc2 . i & di,ci are_homotopic & rng di c= the carrier of U & dom ci = dom di & dom ci = [.(h /. i),(h /. (i + 1)).] ) by A156, A113;
A158: i in dom fc2 by A155, A114, A113, FINSEQ_1:1;
take di ; :: thesis: ex c4 being with_endpoints Curve of (TUnitSphere n) st
( di = fc2 /. i & c4 = fc1 /. i & di,c4 are_homotopic & dom di = dom c4 )

take ci ; :: thesis: ( di = fc2 /. i & ci = fc1 /. i & di,ci are_homotopic & dom di = dom ci )
thus ( di = fc2 /. i & ci = fc1 /. i & di,ci are_homotopic & dom di = dom ci ) by A157, A158, PARTFUN1:def 6; :: thesis: verum
end;
then A159: c0,c are_homotopic by A117, A141, A140, Th44, A114, A115, A31;
A160: dom c0 = [.0,1.]
proof
A161: 0 + 1 < (len fc1) + 1 by A115, A31, XREAL_1:6;
A162: 1 in Seg (len fc1) by A115, A31, FINSEQ_1:1;
set ci = fc1 /. 1;
reconsider ci = fc1 /. 1 as with_endpoints Curve of (TUnitSphere n) by A115, A31, A85;
consider di being with_endpoints Curve of (TUnitSphere n) such that
A163: ( di = fc2 . 1 & di,ci are_homotopic & rng di c= the carrier of U & dom ci = dom di & dom ci = [.(h /. 1),(h /. (1 + 1)).] ) by A162, A113;
1 in Seg (len fc2) by A115, A31, A114, FINSEQ_1:1;
then 1 in dom fc2 by FINSEQ_1:def 3;
then A164: dom (fc2 /. 1) = [.(h /. 1),(h /. (1 + 1)).] by A163, PARTFUN1:def 6;
A165: h /. 1 < h /. (1 + 1) by A69, A115, A31;
1 in Seg (len h) by A161, A31, FINSEQ_1:1;
then A166: 1 in dom h by FINSEQ_1:def 3;
A167: inf (dom (fc2 /. 1)) = h /. 1 by A165, A164, XXREAL_2:25
.= 0 by A5, A166, PARTFUN1:def 6 ;
A168: len fc1 in Seg (len fc1) by A115, A31, FINSEQ_1:1;
set ci1 = fc1 /. (len fc1);
reconsider ci1 = fc1 /. (len fc1) as with_endpoints Curve of (TUnitSphere n) by A115, A31, A85;
consider di1 being with_endpoints Curve of (TUnitSphere n) such that
A169: ( di1 = fc2 . (len fc1) & di1,ci1 are_homotopic & rng di1 c= the carrier of U & dom ci1 = dom di1 & dom ci1 = [.(h /. (len fc1)),(h /. ((len fc1) + 1)).] ) by A168, A113;
len fc1 in Seg (len fc2) by A114, A115, A31, FINSEQ_1:1;
then len fc1 in dom fc2 by FINSEQ_1:def 3;
then A170: dom (fc2 /. (len fc2)) = [.(h /. (len fc1)),(h /. ((len fc1) + 1)).] by A169, A114, PARTFUN1:def 6;
A171: h /. (len fc1) < h /. ((len fc1) + 1) by A69, A115, A31;
len h in Seg (len h) by A161, A31, FINSEQ_1:1;
then A172: len h in dom h by FINSEQ_1:def 3;
A173: sup (dom (fc2 /. (len fc2))) = h /. ((len fc1) + 1) by A171, A170, XXREAL_2:29
.= 1 by A5, A31, A172, PARTFUN1:def 6 ;
thus dom c0 = [.0,1.] by A140, A167, A173; :: thesis: verum
end;
for i being Nat st 1 <= i & i <= len fc2 holds
rng (fc2 /. i) c= the carrier of U
proof
let i be Nat; :: thesis: ( 1 <= i & i <= len fc2 implies rng (fc2 /. i) c= the carrier of U )
assume A174: ( 1 <= i & i <= len fc2 ) ; :: thesis: rng (fc2 /. i) c= the carrier of U
then i in Seg (len fc2) by FINSEQ_1:1;
then A175: i in dom fc2 by FINSEQ_1:def 3;
A176: i in Seg (len fc1) by A114, A174, FINSEQ_1:1;
reconsider c1 = fc1 /. i as with_endpoints Curve of (TUnitSphere n) by A85, A174, A114;
consider c2 being with_endpoints Curve of (TUnitSphere n) such that
A177: ( c2 = fc2 . i & c2,c1 are_homotopic & rng c2 c= the carrier of U & dom c1 = dom c2 & dom c1 = [.(h /. i),(h /. (i + 1)).] ) by A176, A113;
thus rng (fc2 /. i) c= the carrier of U by A175, A177, PARTFUN1:def 6; :: thesis: verum
end;
then A178: rng c0 c= the carrier of U by A140, Th42;
A179: t,t are_connected ;
A180: t = the_first_point_of c by A30, A179, BORSUK_2:def 2
.= the_first_point_of c0 by Th35, A159 ;
A181: t = the_last_point_of c by A30, A179, BORSUK_2:def 2
.= the_last_point_of c0 by Th35, A159 ;
reconsider f0 = c0 as Loop of t by A160, A180, A181, Th28;
A182: f0,f are_homotopic by A159, A179, Th34;
not p in rng f0
proof end;
hence ex g being Loop of t st
( g,f are_homotopic & rng g <> the carrier of (TUnitSphere n) ) by A6, A182; :: thesis: verum