let m, n, i, j be Element of NAT ; for D being non empty Subset of (TOP-REAL 2) st m <= n & 1 < i & i < len (Gauge D,m) & 1 < j & j < width (Gauge D,m) holds
for i1, j1 being Element of NAT st i1 = ((2 |^ (n -' m)) * (i - 2)) + 2 & j1 = ((2 |^ (n -' m)) * (j - 2)) + 2 holds
(Gauge D,m) * i,j = (Gauge D,n) * i1,j1
let D be non empty Subset of (TOP-REAL 2); ( m <= n & 1 < i & i < len (Gauge D,m) & 1 < j & j < width (Gauge D,m) implies for i1, j1 being Element of NAT st i1 = ((2 |^ (n -' m)) * (i - 2)) + 2 & j1 = ((2 |^ (n -' m)) * (j - 2)) + 2 holds
(Gauge D,m) * i,j = (Gauge D,n) * i1,j1 )
assume that
A1:
m <= n
and
A2:
( 1 < i & i < len (Gauge D,m) )
and
A3:
( 1 < j & j < width (Gauge D,m) )
; for i1, j1 being Element of NAT st i1 = ((2 |^ (n -' m)) * (i - 2)) + 2 & j1 = ((2 |^ (n -' m)) * (j - 2)) + 2 holds
(Gauge D,m) * i,j = (Gauge D,n) * i1,j1
let i1, j1 be Element of NAT ; ( i1 = ((2 |^ (n -' m)) * (i - 2)) + 2 & j1 = ((2 |^ (n -' m)) * (j - 2)) + 2 implies (Gauge D,m) * i,j = (Gauge D,n) * i1,j1 )
assume that
A4:
i1 = ((2 |^ (n -' m)) * (i - 2)) + 2
and
A5:
j1 = ((2 |^ (n -' m)) * (j - 2)) + 2
; (Gauge D,m) * i,j = (Gauge D,n) * i1,j1
A6:
( 1 < i1 & i1 < len (Gauge D,n) )
by A1, A2, A4, Th52;
(j - 2) / (2 |^ m) =
(j - 2) / (2 |^ (n -' (n -' m)))
by A1, NAT_D:58
.=
(j - 2) / ((2 |^ n) / (2 |^ (n -' m)))
by NAT_D:50, TOPREAL6:15
.=
(j1 - 2) / (2 |^ n)
by A5, XCMPLX_1:78
;
then A7: (((N-bound D) - (S-bound D)) / (2 |^ m)) * (j - 2) =
((N-bound D) - (S-bound D)) * ((j1 - 2) / (2 |^ n))
by XCMPLX_1:76
.=
(((N-bound D) - (S-bound D)) / (2 |^ n)) * (j1 - 2)
by XCMPLX_1:76
;
(i - 2) / (2 |^ m) =
(i - 2) / (2 |^ (n -' (n -' m)))
by A1, NAT_D:58
.=
(i - 2) / ((2 |^ n) / (2 |^ (n -' m)))
by NAT_D:50, TOPREAL6:15
.=
(i1 - 2) / (2 |^ n)
by A4, XCMPLX_1:78
;
then A8: (((E-bound D) - (W-bound D)) / (2 |^ m)) * (i - 2) =
((E-bound D) - (W-bound D)) * ((i1 - 2) / (2 |^ n))
by XCMPLX_1:76
.=
(((E-bound D) - (W-bound D)) / (2 |^ n)) * (i1 - 2)
by XCMPLX_1:76
;
( 1 < j1 & j1 < width (Gauge D,n) )
by A1, A3, A5, Th53;
then A9:
[i1,j1] in Indices (Gauge D,n)
by A6, MATRIX_1:37;
[i,j] in Indices (Gauge D,m)
by A2, A3, MATRIX_1:37;
hence (Gauge D,m) * i,j =
|[((W-bound D) + ((((E-bound D) - (W-bound D)) / (2 |^ m)) * (i - 2))),((S-bound D) + ((((N-bound D) - (S-bound D)) / (2 |^ m)) * (j - 2)))]|
by JORDAN8:def 1
.=
(Gauge D,n) * i1,j1
by A9, A8, A7, JORDAN8:def 1
;
verum