let f be non constant standard special_circular_sequence; for i being Element of NAT st 1 <= i & i + 2 <= len (GoB f) holds
LSeg (((1 / 2) * (((GoB f) * i,(width (GoB f))) + ((GoB f) * (i + 1),(width (GoB f))))) + |[0 ,1]|),(((1 / 2) * (((GoB f) * (i + 1),(width (GoB f))) + ((GoB f) * (i + 2),(width (GoB f))))) + |[0 ,1]|) misses L~ f
let i be Element of NAT ; ( 1 <= i & i + 2 <= len (GoB f) implies LSeg (((1 / 2) * (((GoB f) * i,(width (GoB f))) + ((GoB f) * (i + 1),(width (GoB f))))) + |[0 ,1]|),(((1 / 2) * (((GoB f) * (i + 1),(width (GoB f))) + ((GoB f) * (i + 2),(width (GoB f))))) + |[0 ,1]|) misses L~ f )
assume that
A1:
1 <= i
and
A2:
i + 2 <= len (GoB f)
; LSeg (((1 / 2) * (((GoB f) * i,(width (GoB f))) + ((GoB f) * (i + 1),(width (GoB f))))) + |[0 ,1]|),(((1 / 2) * (((GoB f) * (i + 1),(width (GoB f))) + ((GoB f) * (i + 2),(width (GoB f))))) + |[0 ,1]|) misses L~ f
A3:
1 <= width (GoB f)
by GOBOARD7:35;
now A4:
i <= i + 2
by NAT_1:11;
then
i <= len (GoB f)
by A2, XXREAL_0:2;
then A5:
((GoB f) * i,(width (GoB f))) `2 = ((GoB f) * 1,(width (GoB f))) `2
by A1, A3, GOBOARD5:2;
i + 1
<= i + 2
by XREAL_1:8;
then
( 1
<= i + 1 &
i + 1
<= len (GoB f) )
by A2, NAT_1:11, XXREAL_0:2;
then A6:
((GoB f) * (i + 1),(width (GoB f))) `2 = ((GoB f) * 1,(width (GoB f))) `2
by A3, GOBOARD5:2;
1
<= i + 2
by A1, A4, XXREAL_0:2;
then A7:
((GoB f) * (i + 2),(width (GoB f))) `2 = ((GoB f) * 1,(width (GoB f))) `2
by A2, A3, GOBOARD5:2;
(((1 / 2) * (((GoB f) * (i + 1),(width (GoB f))) + ((GoB f) * (i + 2),(width (GoB f))))) + |[0 ,1]|) `2 =
(((1 / 2) * (((GoB f) * (i + 1),(width (GoB f))) + ((GoB f) * (i + 2),(width (GoB f))))) `2 ) + (|[0 ,1]| `2 )
by TOPREAL3:7
.=
((1 / 2) * ((((GoB f) * (i + 1),(width (GoB f))) + ((GoB f) * (i + 2),(width (GoB f)))) `2 )) + (|[0 ,1]| `2 )
by TOPREAL3:9
.=
((1 / 2) * ((((GoB f) * 1,(width (GoB f))) `2 ) + (((GoB f) * 1,(width (GoB f))) `2 ))) + (|[0 ,1]| `2 )
by A6, A7, TOPREAL3:7
.=
(1 * (((GoB f) * 1,(width (GoB f))) `2 )) + 1
by EUCLID:56
;
then A8:
((1 / 2) * (((GoB f) * (i + 1),(width (GoB f))) + ((GoB f) * (i + 2),(width (GoB f))))) + |[0 ,1]| = |[((((1 / 2) * (((GoB f) * (i + 1),(width (GoB f))) + ((GoB f) * (i + 2),(width (GoB f))))) + |[0 ,1]|) `1 ),((((GoB f) * 1,(width (GoB f))) `2 ) + 1)]|
by EUCLID:57;
(((1 / 2) * (((GoB f) * i,(width (GoB f))) + ((GoB f) * (i + 1),(width (GoB f))))) + |[0 ,1]|) `2 =
(((1 / 2) * (((GoB f) * i,(width (GoB f))) + ((GoB f) * (i + 1),(width (GoB f))))) `2 ) + (|[0 ,1]| `2 )
by TOPREAL3:7
.=
((1 / 2) * ((((GoB f) * i,(width (GoB f))) + ((GoB f) * (i + 1),(width (GoB f)))) `2 )) + (|[0 ,1]| `2 )
by TOPREAL3:9
.=
((1 / 2) * ((((GoB f) * 1,(width (GoB f))) `2 ) + (((GoB f) * 1,(width (GoB f))) `2 ))) + (|[0 ,1]| `2 )
by A5, A6, TOPREAL3:7
.=
(1 * (((GoB f) * 1,(width (GoB f))) `2 )) + 1
by EUCLID:56
;
then A9:
((1 / 2) * (((GoB f) * i,(width (GoB f))) + ((GoB f) * (i + 1),(width (GoB f))))) + |[0 ,1]| = |[((((1 / 2) * (((GoB f) * i,(width (GoB f))) + ((GoB f) * (i + 1),(width (GoB f))))) + |[0 ,1]|) `1 ),((((GoB f) * 1,(width (GoB f))) `2 ) + 1)]|
by EUCLID:57;
let p be
Point of
(TOP-REAL 2);
( p in LSeg (((1 / 2) * (((GoB f) * i,(width (GoB f))) + ((GoB f) * (i + 1),(width (GoB f))))) + |[0 ,1]|),(((1 / 2) * (((GoB f) * (i + 1),(width (GoB f))) + ((GoB f) * (i + 2),(width (GoB f))))) + |[0 ,1]|) implies p `2 > ((GoB f) * 1,(width (GoB f))) `2 )assume
p in LSeg (((1 / 2) * (((GoB f) * i,(width (GoB f))) + ((GoB f) * (i + 1),(width (GoB f))))) + |[0 ,1]|),
(((1 / 2) * (((GoB f) * (i + 1),(width (GoB f))) + ((GoB f) * (i + 2),(width (GoB f))))) + |[0 ,1]|)
;
p `2 > ((GoB f) * 1,(width (GoB f))) `2 then
p `2 = (((GoB f) * 1,(width (GoB f))) `2 ) + 1
by A9, A8, TOPREAL3:18;
hence
p `2 > ((GoB f) * 1,(width (GoB f))) `2
by XREAL_1:31;
verum end;
hence
LSeg (((1 / 2) * (((GoB f) * i,(width (GoB f))) + ((GoB f) * (i + 1),(width (GoB f))))) + |[0 ,1]|),(((1 / 2) * (((GoB f) * (i + 1),(width (GoB f))) + ((GoB f) * (i + 2),(width (GoB f))))) + |[0 ,1]|) misses L~ f
by Th24; verum