let D be non empty set ; for f being FinSequence of D st f is weakly-one-to-one & f is circular holds
for p being Element of D holds Rotate (f,p) is weakly-one-to-one
let f be FinSequence of D; ( f is weakly-one-to-one & f is circular implies for p being Element of D holds Rotate (f,p) is weakly-one-to-one )
assume A1:
( f is weakly-one-to-one & f is circular )
; for p being Element of D holds Rotate (f,p) is weakly-one-to-one
let p be Element of D; Rotate (f,p) is weakly-one-to-one
per cases
( p in rng f or not p in rng f )
;
suppose A2:
p in rng f
;
Rotate (f,p) is weakly-one-to-one then A3:
p .. f <= len f
by FINSEQ_4:21;
A4:
len (f :- p) = ((len f) - (p .. f)) + 1
by A2, FINSEQ_5:50;
let i be
Nat;
JORDAN23:def 2 ( 1 <= i & i < len (Rotate (f,p)) implies (Rotate (f,p)) . i <> (Rotate (f,p)) . (i + 1) )
1
<= p .. f
by A2, FINSEQ_4:21;
then A5:
(i -' 1) + (p .. f) >= 0 + 1
by XREAL_1:7;
then A6:
((i -' 1) + (p .. f)) + 1
> 1
by NAT_1:13;
assume that A7:
1
<= i
and A8:
i < len (Rotate (f,p))
;
(Rotate (f,p)) . i <> (Rotate (f,p)) . (i + 1)A9:
i + 1
> 1
by A7, NAT_1:13;
(i - 1) + 1
>= 1
by A7;
then A10:
i - 1
>= 1
- 1
by XREAL_1:20;
A11:
((i + 1) -' 1) + (p .. f) =
((i + 1) - 1) + (p .. f)
by A7, XREAL_0:def 2
.=
((i - 1) + (p .. f)) + 1
.=
((i -' 1) + (p .. f)) + 1
by A10, XREAL_0:def 2
;
A12:
i + 1
<= len (Rotate (f,p))
by A8, NAT_1:13;
A13:
len (Rotate (f,p)) = len f
by FINSEQ_6:179;
then A14:
len f > 1
by A7, A8, XXREAL_0:2;
then A15:
len f >= 1
+ 1
by NAT_1:13;
now (Rotate (f,p)) . i <> (Rotate (f,p)) . (i + 1)per cases
( i < len (f :- p) or i = len (f :- p) or i > len (f :- p) )
by XXREAL_0:1;
suppose A16:
i < len (f :- p)
;
(Rotate (f,p)) . i <> (Rotate (f,p)) . (i + 1)then
i - 1
< (len f) - (p .. f)
by A4, XREAL_1:19;
then
(i - 1) + (p .. f) < len f
by XREAL_1:20;
then A17:
(i -' 1) + (p .. f) < len f
by A10, XREAL_0:def 2;
then A18:
((i -' 1) + (p .. f)) + 1
<= len f
by NAT_1:13;
(Rotate (f,p)) /. i =
f /. ((i -' 1) + (p .. f))
by A2, A7, A16, FINSEQ_6:174
.=
f . ((i -' 1) + (p .. f))
by A5, A17, FINSEQ_4:15
;
then A19:
(Rotate (f,p)) . i = f . ((i -' 1) + (p .. f))
by A7, A8, FINSEQ_4:15;
i + 1
<= len (f :- p)
by A16, NAT_1:13;
then (Rotate (f,p)) /. (i + 1) =
f /. (((i + 1) -' 1) + (p .. f))
by A2, A9, FINSEQ_6:174
.=
f . (((i + 1) -' 1) + (p .. f))
by A6, A11, A18, FINSEQ_4:15
;
then
(Rotate (f,p)) . (i + 1) = f . (((i + 1) -' 1) + (p .. f))
by A9, A12, FINSEQ_4:15;
hence
(Rotate (f,p)) . i <> (Rotate (f,p)) . (i + 1)
by A1, A5, A11, A17, A19;
verum end; suppose A20:
i = len (f :- p)
;
(Rotate (f,p)) . i <> (Rotate (f,p)) . (i + 1)then (Rotate (f,p)) /. i =
f /. (len f)
by A2, FINSEQ_6:176
.=
f /. 1
by A1, FINSEQ_6:def 1
.=
f . 1
by A14, FINSEQ_4:15
;
then A21:
(Rotate (f,p)) . i = f . 1
by A7, A8, FINSEQ_4:15;
A22:
((i + 1) + (p .. f)) -' (len f) =
((len f) + (1 + 1)) - (len f)
by A4, A20, XREAL_0:def 2
.=
2
;
i + 1
> len (f :- p)
by A20, NAT_1:13;
then (Rotate (f,p)) /. (i + 1) =
f /. (((i + 1) + (p .. f)) -' (len f))
by A2, A13, A12, FINSEQ_6:177
.=
f . (((i + 1) + (p .. f)) -' (len f))
by A15, A22, FINSEQ_4:15
;
then
(Rotate (f,p)) . (i + 1) = f . (1 + 1)
by A9, A12, A22, FINSEQ_4:15;
hence
(Rotate (f,p)) . i <> (Rotate (f,p)) . (i + 1)
by A1, A14, A21;
verum end; suppose A23:
i > len (f :- p)
;
(Rotate (f,p)) . i <> (Rotate (f,p)) . (i + 1)then A24:
i - ((len f) - (p .. f)) > 1
by A4, XREAL_1:20;
then
(i + (p .. f)) - (len f) > 1
- 1
by XXREAL_0:2;
then A25:
((i + (p .. f)) - (len f)) + 1
> 1
by XREAL_1:19;
then A26:
((i + 1) + (p .. f)) -' (len f) =
((i + 1) + (p .. f)) - (len f)
by XREAL_0:def 2
.=
((i + (p .. f)) - (len f)) + 1
.=
((i + (p .. f)) -' (len f)) + 1
by A24, XREAL_0:def 2
;
(i + 1) + (p .. f) <= (len f) + (len f)
by A3, A13, A12, XREAL_1:7;
then
((i + 1) + (p .. f)) - (len f) <= len f
by XREAL_1:20;
then A27:
((i + 1) + (p .. f)) -' (len f) <= len f
by A25, XREAL_0:def 2;
((i + 1) + (p .. f)) - (len f) > 1
by A25;
then A28:
((i + 1) + (p .. f)) -' (len f) > 1
by XREAL_0:def 2;
i + 1
> len (f :- p)
by A23, NAT_1:13;
then (Rotate (f,p)) /. (i + 1) =
f /. (((i + 1) + (p .. f)) -' (len f))
by A2, A13, A12, FINSEQ_6:177
.=
f . (((i + 1) + (p .. f)) -' (len f))
by A28, A27, FINSEQ_4:15
;
then A29:
(Rotate (f,p)) . (i + 1) = f . (((i + 1) + (p .. f)) -' (len f))
by A9, A12, FINSEQ_4:15;
(i + (p .. f)) - (len f) > 1
by A24;
then A30:
(i + (p .. f)) -' (len f) > 1
by XREAL_0:def 2;
i + (p .. f) < (len f) + (len f)
by A3, A13, A8, XREAL_1:8;
then
(i + (p .. f)) - (len f) < len f
by XREAL_1:19;
then A31:
(i + (p .. f)) -' (len f) < len f
by A24, XREAL_0:def 2;
(Rotate (f,p)) /. i =
f /. ((i + (p .. f)) -' (len f))
by A2, A13, A8, A23, FINSEQ_6:177
.=
f . ((i + (p .. f)) -' (len f))
by A30, A31, FINSEQ_4:15
;
then
(Rotate (f,p)) . i = f . ((i + (p .. f)) -' (len f))
by A7, A8, FINSEQ_4:15;
hence
(Rotate (f,p)) . i <> (Rotate (f,p)) . (i + 1)
by A1, A30, A31, A29, A26;
verum end; end; end; hence
(Rotate (f,p)) . i <> (Rotate (f,p)) . (i + 1)
;
verum end; end;