let m, i, n be Element of NAT ; :: thesis: for D being compact non horizontal non vertical Subset of (TOP-REAL 2)
for k being Element of NAT st 2 <= m & m + 1 < len (Gauge D,i) & 2 <= n & n + 1 < len (Gauge D,i) holds
cell (Gauge D,i),m,n = union { (cell (Gauge D,(i + k)),a,b) where a, b is Element of NAT : ( (((2 |^ k) * m) - (2 |^ (k + 1))) + 2 <= a & a <= (((2 |^ k) * m) - (2 |^ k)) + 1 & (((2 |^ k) * n) - (2 |^ (k + 1))) + 2 <= b & b <= (((2 |^ k) * n) - (2 |^ k)) + 1 ) }
let D be compact non horizontal non vertical Subset of (TOP-REAL 2); :: thesis: for k being Element of NAT st 2 <= m & m + 1 < len (Gauge D,i) & 2 <= n & n + 1 < len (Gauge D,i) holds
cell (Gauge D,i),m,n = union { (cell (Gauge D,(i + k)),a,b) where a, b is Element of NAT : ( (((2 |^ k) * m) - (2 |^ (k + 1))) + 2 <= a & a <= (((2 |^ k) * m) - (2 |^ k)) + 1 & (((2 |^ k) * n) - (2 |^ (k + 1))) + 2 <= b & b <= (((2 |^ k) * n) - (2 |^ k)) + 1 ) }
let k be Element of NAT ; :: thesis: ( 2 <= m & m + 1 < len (Gauge D,i) & 2 <= n & n + 1 < len (Gauge D,i) implies cell (Gauge D,i),m,n = union { (cell (Gauge D,(i + k)),a,b) where a, b is Element of NAT : ( (((2 |^ k) * m) - (2 |^ (k + 1))) + 2 <= a & a <= (((2 |^ k) * m) - (2 |^ k)) + 1 & (((2 |^ k) * n) - (2 |^ (k + 1))) + 2 <= b & b <= (((2 |^ k) * n) - (2 |^ k)) + 1 ) } )
assume that
A1:
2 <= m
and
A2:
m + 1 < len (Gauge D,i)
and
A3:
2 <= n
and
A4:
n + 1 < len (Gauge D,i)
; :: thesis: cell (Gauge D,i),m,n = union { (cell (Gauge D,(i + k)),a,b) where a, b is Element of NAT : ( (((2 |^ k) * m) - (2 |^ (k + 1))) + 2 <= a & a <= (((2 |^ k) * m) - (2 |^ k)) + 1 & (((2 |^ k) * n) - (2 |^ (k + 1))) + 2 <= b & b <= (((2 |^ k) * n) - (2 |^ k)) + 1 ) }
deffunc H1( Element of NAT ) -> set = { (cell (Gauge D,(i + $1)),a,b) where a, b is Element of NAT : ( (((2 |^ $1) * m) - (2 |^ ($1 + 1))) + 2 <= a & a <= (((2 |^ $1) * m) - (2 |^ $1)) + 1 & (((2 |^ $1) * n) - (2 |^ ($1 + 1))) + 2 <= b & b <= (((2 |^ $1) * n) - (2 |^ $1)) + 1 ) } ;
defpred S1[ Element of NAT ] means cell (Gauge D,i),m,n = union H1($1);
A5:
S1[ 0 ]
proof
H1(
0 )
= {(cell (Gauge D,i),m,n)}
proof
hereby :: according to TARSKI:def 3,
XBOOLE_0:def 10 :: thesis: {(cell (Gauge D,i),m,n)} c= H1( 0 )
let x be
set ;
:: thesis: ( x in H1( 0 ) implies x in {(cell (Gauge D,i),m,n)} )assume
x in H1(
0 )
;
:: thesis: x in {(cell (Gauge D,i),m,n)}then consider a,
b being
Element of
NAT such that A8:
x = cell (Gauge D,(i + 0 )),
a,
b
and A9:
(
(((2 |^ 0 ) * m) - (2 |^ (0 + 1))) + 2
<= a &
a <= (((2 |^ 0 ) * m) - (2 |^ 0 )) + 1 &
(((2 |^ 0 ) * n) - (2 |^ (0 + 1))) + 2
<= b &
b <= (((2 |^ 0 ) * n) - (2 |^ 0 )) + 1 )
;
then
(
a = m &
b = n )
by A9;
hence
x in {(cell (Gauge D,i),m,n)}
by A8, TARSKI:def 1;
:: thesis: verum
end;
let x be
set ;
:: according to TARSKI:def 3 :: thesis: ( not x in {(cell (Gauge D,i),m,n)} or x in H1( 0 ) )
assume
x in {(cell (Gauge D,i),m,n)}
;
:: thesis: x in H1( 0 )
then A11:
x = cell (Gauge D,(i + 0 )),
m,
n
by TARSKI:def 1;
(
(((2 |^ 0 ) * m) - (2 |^ (0 + 1))) + 2
<= m &
m <= (((2 |^ 0 ) * m) - (2 |^ 0 )) + 1 &
(((2 |^ 0 ) * n) - (2 |^ (0 + 1))) + 2
<= n &
n <= (((2 |^ 0 ) * n) - (2 |^ 0 )) + 1 )
by A6;
hence
x in H1(
0 )
by A11;
:: thesis: verum
end;
hence
S1[
0 ]
by ZFMISC_1:31;
:: thesis: verum
end;
A12:
for w being Element of NAT st S1[w] holds
S1[w + 1]
proof
let w be
Element of
NAT ;
:: thesis: ( S1[w] implies S1[w + 1] )
assume A13:
S1[
w]
;
:: thesis: S1[w + 1]
A14:
(i + w) + 1
= i + (w + 1)
;
A15:
len (Gauge D,(i + w)) = (2 |^ (i + w)) + 3
by JORDAN8:def 1;
A16:
len (Gauge D,i) = (2 |^ i) + 3
by JORDAN8:def 1;
for
x being
set st
x in H1(
w) holds
ex
K being
set st
(
K c= H1(
w + 1) &
x c= union K )
proof
let x be
set ;
:: thesis: ( x in H1(w) implies ex K being set st
( K c= H1(w + 1) & x c= union K ) )
assume
x in H1(
w)
;
:: thesis: ex K being set st
( K c= H1(w + 1) & x c= union K )
then consider a,
b being
Element of
NAT such that A17:
x = cell (Gauge D,(i + w)),
a,
b
and A18:
(((2 |^ w) * m) - (2 |^ (w + 1))) + 2
<= a
and A19:
a <= (((2 |^ w) * m) - (2 |^ w)) + 1
and A20:
(((2 |^ w) * n) - (2 |^ (w + 1))) + 2
<= b
and A21:
b <= (((2 |^ w) * n) - (2 |^ w)) + 1
;
then A22:
( 2
<= (((2 |^ w) * m) - (2 |^ (w + 1))) + 2 & 2
<= (((2 |^ w) * n) - (2 |^ (w + 1))) + 2 )
by A1, A3;
then A23:
2
<= a
by A18, XXREAL_0:2;
A24:
2
<= b
by A20, A22, XXREAL_0:2;
A25:
(2 * a) -' 1
= (2 * a) - 1
by A23, Lm8, XXREAL_0:2;
A26:
(2 * b) -' 1
= (2 * b) - 1
by A24, Lm8, XXREAL_0:2;
A27:
(2 * a) -' 2
= (2 * a) - 2
by A18, A22, Lm7, XXREAL_0:2;
A28:
(2 * b) -' 2
= (2 * b) - 2
by A20, A22, Lm7, XXREAL_0:2;
A29:
(2 * a) -' 2
< (2 * a) -' 1
by A25, A27, XREAL_1:17;
A30:
(2 * b) -' 2
< (2 * b) -' 1
by A26, A28, XREAL_1:17;
take K =
{(cell (Gauge D,((i + w) + 1)),((2 * a) -' 2),((2 * b) -' 2)),(cell (Gauge D,((i + w) + 1)),((2 * a) -' 1),((2 * b) -' 2)),(cell (Gauge D,((i + w) + 1)),((2 * a) -' 2),((2 * b) -' 1)),(cell (Gauge D,((i + w) + 1)),((2 * a) -' 1),((2 * b) -' 1))};
:: thesis: ( K c= H1(w + 1) & x c= union K )
hereby :: according to TARSKI:def 3 :: thesis: x c= union K
let q be
set ;
:: thesis: ( q in K implies q in H1(w + 1) )assume A31:
q in K
;
:: thesis: q in H1(w + 1)then A37:
(((2 |^ (w + 1)) * m) - (2 |^ ((w + 1) + 1))) + 2
<= (2 * a) -' 2
by A18, A23;
A38:
(2 * a) -' 2
< (((2 |^ (w + 1)) * m) - (2 |^ (w + 1))) + 1
by A19, A23, A32;
then
((2 * a) -' 2) + 1
<= (((2 |^ (w + 1)) * m) - (2 |^ (w + 1))) + 1
by INT_1:20;
then A39:
(2 * a) -' 1
<= (((2 |^ (w + 1)) * m) - (2 |^ (w + 1))) + 1
by A23, Lm9, XXREAL_0:2;
A40:
(((2 |^ (w + 1)) * n) - (2 |^ ((w + 1) + 1))) + 2
<= (2 * b) -' 2
by A20, A24, A35;
A41:
(2 * b) -' 2
< (((2 |^ (w + 1)) * n) - (2 |^ (w + 1))) + 1
by A21, A24, A32;
then
((2 * b) -' 2) + 1
<= (((2 |^ (w + 1)) * n) - (2 |^ (w + 1))) + 1
by INT_1:20;
then A42:
(2 * b) -' 1
<= (((2 |^ (w + 1)) * n) - (2 |^ (w + 1))) + 1
by A24, Lm9, XXREAL_0:2;
A43:
(((2 |^ (w + 1)) * m) - (2 |^ ((w + 1) + 1))) + 2
<= (2 * a) -' 1
by A29, A37, XXREAL_0:2;
A44:
(((2 |^ (w + 1)) * n) - (2 |^ ((w + 1) + 1))) + 2
<= (2 * b) -' 1
by A30, A40, XXREAL_0:2;
(
q = cell (Gauge D,(i + (w + 1))),
((2 * a) -' 2),
((2 * b) -' 2) or
q = cell (Gauge D,(i + (w + 1))),
((2 * a) -' 1),
((2 * b) -' 2) or
q = cell (Gauge D,(i + (w + 1))),
((2 * a) -' 2),
((2 * b) -' 1) or
q = cell (Gauge D,(i + (w + 1))),
((2 * a) -' 1),
((2 * b) -' 1) )
by A31, ENUMSET1:def 2;
hence
q in H1(
w + 1)
by A37, A38, A39, A40, A41, A42, A43, A44;
:: thesis: verum
end;
now let a,
m be
Element of
NAT ;
:: thesis: ( m + 1 < len (Gauge D,i) & a <= (((2 |^ w) * m) - (2 |^ w)) + 1 implies a + 1 < len (Gauge D,(i + w)) )assume
m + 1
< len (Gauge D,i)
;
:: thesis: ( a <= (((2 |^ w) * m) - (2 |^ w)) + 1 implies a + 1 < len (Gauge D,(i + w)) )then
(m + 1) - 2
< ((2 |^ i) + 3) - 2
by A16, XREAL_1:11;
then
m - 1
< (2 |^ i) + (3 - 2)
;
then
m - 1
<= (2 |^ i) + 0
by INT_1:20;
then
(2 |^ w) * (m - 1) <= (2 |^ w) * (2 |^ i)
by XREAL_1:66;
then
(2 |^ w) * (m - 1) <= 2
|^ (w + i)
by NEWTON:13;
then A45:
((2 |^ w) * (m - 1)) + 3
<= (2 |^ (w + i)) + 3
by XREAL_1:8;
assume
a <= (((2 |^ w) * m) - (2 |^ w)) + 1
;
:: thesis: a + 1 < len (Gauge D,(i + w))then
a + 1
<= ((((2 |^ w) * m) - (2 |^ w)) + 1) + 1
by XREAL_1:8;
then
a + 1
< (((((2 |^ w) * m) - (2 |^ w)) + 1) + 1) + 1
by XREAL_1:147;
hence
a + 1
< len (Gauge D,(i + w))
by A15, A45, XXREAL_0:2;
:: thesis: verum end;
then
(
a + 1
< len (Gauge D,(i + w)) &
b + 1
< len (Gauge D,(i + w)) )
by A2, A4, A19, A21;
then
cell (Gauge D,(i + w)),
a,
b = (((cell (Gauge D,((i + w) + 1)),((2 * a) -' 2),((2 * b) -' 2)) \/ (cell (Gauge D,((i + w) + 1)),((2 * a) -' 1),((2 * b) -' 2))) \/ (cell (Gauge D,((i + w) + 1)),((2 * a) -' 2),((2 * b) -' 1))) \/ (cell (Gauge D,((i + w) + 1)),((2 * a) -' 1),((2 * b) -' 1))
by A23, A24, Th9;
hence
x c= union K
by A17, Lm4;
:: thesis: verum
end;
hence
cell (Gauge D,i),
m,
n c= union H1(
w + 1)
by A13, Th1;
:: according to XBOOLE_0:def 10 :: thesis: union H1(w + 1) c= cell (Gauge D,i),m,n
H1(
w + 1)
is_finer_than H1(
w)
proof
let X be
set ;
:: according to SETFAM_1:def 2 :: thesis: ( not X in H1(w + 1) or ex b1 being set st
( b1 in H1(w) & X c= b1 ) )
assume
X in H1(
w + 1)
;
:: thesis: ex b1 being set st
( b1 in H1(w) & X c= b1 )
then consider a,
b being
Element of
NAT such that A46:
X = cell (Gauge D,(i + (w + 1))),
a,
b
and A47:
(((2 |^ (w + 1)) * m) - (2 |^ ((w + 1) + 1))) + 2
<= a
and A48:
a <= (((2 |^ (w + 1)) * m) - (2 |^ (w + 1))) + 1
and A49:
(((2 |^ (w + 1)) * n) - (2 |^ ((w + 1) + 1))) + 2
<= b
and A50:
b <= (((2 |^ (w + 1)) * n) - (2 |^ (w + 1))) + 1
;
deffunc H2(
Element of
NAT ,
Element of
NAT )
-> Element of
K10(the
carrier of
(TOP-REAL 2)) =
cell (Gauge D,((i + w) + 1)),
((2 * ((a div 2) + 1)) -' $1),
((2 * ((b div 2) + 1)) -' $2);
then
2
<= (((2 |^ (w + 1)) * m) - (2 |^ ((w + 1) + 1))) + 2
by A1;
then A58:
2
<= a
by A47, XXREAL_0:2;
2
<= (((2 |^ (w + 1)) * n) - (2 |^ ((w + 1) + 1))) + 2
by A3, A56;
then A59:
2
<= b
by A49, XXREAL_0:2;
take Y =
cell (Gauge D,(i + w)),
((a div 2) + 1),
((b div 2) + 1);
:: thesis: ( Y in H1(w) & X c= Y )
2
div 2
<= a div 2
by A58, NAT_2:26;
then A60:
1
+ 1
<= (a div 2) + 1
by Lm2, XREAL_1:8;
A63:
now let a,
m be
Element of
NAT ;
:: thesis: ( m + 1 < len (Gauge D,i) & a <= (((2 |^ (w + 1)) * m) - (2 |^ (w + 1))) + 1 implies ((a div 2) + 1) + 1 < len (Gauge D,(i + w)) )assume A64:
m + 1
< len (Gauge D,i)
;
:: thesis: ( a <= (((2 |^ (w + 1)) * m) - (2 |^ (w + 1))) + 1 implies ((a div 2) + 1) + 1 < len (Gauge D,(i + w)) )assume
a <= (((2 |^ (w + 1)) * m) - (2 |^ (w + 1))) + 1
;
:: thesis: ((a div 2) + 1) + 1 < len (Gauge D,(i + w))then
a + 3
<= ((((2 |^ (w + 1)) * m) - (2 |^ (w + 1))) + 1) + 3
by XREAL_1:8;
then A65:
(a + 3) + 0 < (((((2 |^ (w + 1)) * m) - (2 |^ (w + 1))) + 1) + 3) + 1
by XREAL_1:10;
then A66:
(a + 3) + 1
<= (((((2 |^ (w + 1)) * m) - (2 |^ (w + 1))) + 1) + 3) + 1
by INT_1:20;
m + 1
< (2 |^ i) + 3
by A64, JORDAN8:def 1;
then
(2 * (m + 1)) -' 2
< (2 |^ (i + 1)) + 3
by Lm13;
then
((2 * m) + (2 * 1)) -' 2
< (2 |^ (i + 1)) + 3
;
then
2
* m < (2 |^ (i + 1)) + 3
by NAT_D:34;
then
(1 / 2) * (2 * m) < (1 / 2) * ((2 |^ (i + 1)) + 3)
by XREAL_1:70;
then
m < ((1 / 2) * (2 |^ (i + 1))) + ((1 / 2) * 3)
;
then A67:
m < (2 |^ i) + ((1 / 2) * 3)
by Th2;
(2 |^ i) + (3 / 2) < (2 |^ i) + 2
by XREAL_1:8;
then
m < (2 |^ i) + 2
by A67, XXREAL_0:2;
then
m + 1
<= (2 |^ i) + 2
by NAT_1:13;
then
(m + 1) - 2
<= ((2 |^ i) + 2) - 2
by XREAL_1:11;
then
(2 |^ (w + 1)) * (m - 1) <= (2 |^ (w + 1)) * (2 |^ i)
by XREAL_1:66;
then
((2 |^ (w + 1)) * (m - 1)) + 5
< ((2 |^ (w + 1)) * (2 |^ i)) + 6
by XREAL_1:10;
then A68:
((2 |^ (w + 1)) * (m - 1)) + 5
< (2 |^ ((w + 1) + i)) + 6
by NEWTON:13;
then A69:
(((2 |^ (w + 1)) * (m - 1)) + 1) + (3 + 1) < (2 * (2 |^ (i + w))) + 6
by A14, NEWTON:11;
A70:
((((2 |^ (w + 1)) * (m - 1)) + 1) + 3) + 1
< (2 * (2 |^ (i + w))) + (2 * 3)
by A14, A68, NEWTON:11;
hence
((a div 2) + 1) + 1
< len (Gauge D,(i + w))
by A15, XREAL_1:66;
:: thesis: verum end;
then A73:
((a div 2) + 1) + 1
< len (Gauge D,(i + w))
by A2, A48;
2
div 2
<= b div 2
by A59, NAT_2:26;
then A74:
1
+ 1
<= (b div 2) + 1
by Lm2, XREAL_1:8;
((b div 2) + 1) + 1
< len (Gauge D,(i + w))
by A4, A50, A63;
then A75:
Y = ((H2(2,2) \/ H2(1,2)) \/ H2(2,1)) \/ H2(1,1)
by A60, A73, A74, Th9;
per cases
( ( not a is even & not b is even ) or ( not a is even & b is even ) or ( a is even & not b is even ) or ( a is even & b is even ) )
;
suppose A88:
( not
a is
even & not
b is
even )
;
:: thesis: ( Y in H1(w) & X c= Y )then A89:
(2 * ((a div 2) + 1)) -' 1 =
(a + 1) -' 1
by A53
.=
a
by NAT_D:34
;
A90:
(((2 |^ w) * m) - (2 |^ (w + 1))) + 2
<= (a div 2) + 1
by A47, A82, A88;
A91:
(a div 2) + 1
<= (((2 |^ w) * m) - (2 |^ w)) + 1
by A48, A85, A88;
A92:
(((2 |^ w) * n) - (2 |^ (w + 1))) + 2
<= (b div 2) + 1
by A49, A82, A88;
(b div 2) + 1
<= (((2 |^ w) * n) - (2 |^ w)) + 1
by A50, A85, A88;
hence
Y in H1(
w)
by A90, A91, A92;
:: thesis: X c= Y(2 * ((b div 2) + 1)) -' 1 =
(b + 1) -' 1
by A53, A88
.=
b
by NAT_D:34
;
hence
X c= Y
by A46, A75, A89, XBOOLE_1:7;
:: thesis: verum end; suppose A93:
( not
a is
even &
b is
even )
;
:: thesis: ( Y in H1(w) & X c= Y )then A94:
(2 * ((a div 2) + 1)) -' 1 =
(a + 1) -' 1
by A53
.=
a
by NAT_D:34
;
A95:
(2 * ((b div 2) + 1)) -' 2 =
(b + 2) -' 2
by A51, A93
.=
b
by NAT_D:34
;
A96:
(((2 |^ w) * m) - (2 |^ (w + 1))) + 2
<= (a div 2) + 1
by A47, A82, A93;
A97:
(a div 2) + 1
<= (((2 |^ w) * m) - (2 |^ w)) + 1
by A48, A85, A93;
A98:
(((2 |^ w) * n) - (2 |^ (w + 1))) + 2
<= (b div 2) + 1
by A49, A76, A93;
(b div 2) + 1
<= (((2 |^ w) * n) - (2 |^ w)) + 1
by A50, A79, A93;
hence
Y in H1(
w)
by A96, A97, A98;
:: thesis: X c= YA99:
H2(1,2)
c= H2(2,2)
\/ H2(1,2)
by XBOOLE_1:7;
H2(2,2)
\/ H2(1,2)
c= (H2(2,2) \/ H2(1,2)) \/ H2(2,1)
by XBOOLE_1:7;
then A100:
H2(1,2)
c= (H2(2,2) \/ H2(1,2)) \/ H2(2,1)
by A99, XBOOLE_1:1;
(H2(2,2) \/ H2(1,2)) \/ H2(2,1)
c= Y
by A75, XBOOLE_1:7;
hence
X c= Y
by A46, A94, A95, A100, XBOOLE_1:1;
:: thesis: verum end; suppose A101:
(
a is
even & not
b is
even )
;
:: thesis: ( Y in H1(w) & X c= Y )then A102:
(2 * ((a div 2) + 1)) -' 2 =
(a + 2) -' 2
by A51
.=
a
by NAT_D:34
;
A103:
(2 * ((b div 2) + 1)) -' 1 =
(b + 1) -' 1
by A53, A101
.=
b
by NAT_D:34
;
A104:
(((2 |^ w) * m) - (2 |^ (w + 1))) + 2
<= (a div 2) + 1
by A47, A76, A101;
A105:
(a div 2) + 1
<= (((2 |^ w) * m) - (2 |^ w)) + 1
by A48, A79, A101;
A106:
(((2 |^ w) * n) - (2 |^ (w + 1))) + 2
<= (b div 2) + 1
by A49, A82, A101;
(b div 2) + 1
<= (((2 |^ w) * n) - (2 |^ w)) + 1
by A50, A85, A101;
hence
Y in H1(
w)
by A104, A105, A106;
:: thesis: X c= YA107:
H2(2,1)
c= (H2(2,2) \/ H2(1,2)) \/ H2(2,1)
by XBOOLE_1:7;
(H2(2,2) \/ H2(1,2)) \/ H2(2,1)
c= Y
by A75, XBOOLE_1:7;
hence
X c= Y
by A46, A102, A103, A107, XBOOLE_1:1;
:: thesis: verum end; suppose A108:
(
a is
even &
b is
even )
;
:: thesis: ( Y in H1(w) & X c= Y )then A109:
(2 * ((a div 2) + 1)) -' 2 =
(a + 2) -' 2
by A51
.=
a
by NAT_D:34
;
A110:
(((2 |^ w) * m) - (2 |^ (w + 1))) + 2
<= (a div 2) + 1
by A47, A76, A108;
A111:
(a div 2) + 1
<= (((2 |^ w) * m) - (2 |^ w)) + 1
by A48, A79, A108;
A112:
(((2 |^ w) * n) - (2 |^ (w + 1))) + 2
<= (b div 2) + 1
by A49, A76, A108;
(b div 2) + 1
<= (((2 |^ w) * n) - (2 |^ w)) + 1
by A50, A79, A108;
hence
Y in H1(
w)
by A110, A111, A112;
:: thesis: X c= Y(2 * ((b div 2) + 1)) -' 2 =
(b + 2) -' 2
by A51, A108
.=
b
by NAT_D:34
;
then
X c= H2(2,2)
\/ ((H2(1,2) \/ H2(2,1)) \/ H2(1,1))
by A46, A109, XBOOLE_1:7;
then
X c= (H2(2,2) \/ (H2(1,2) \/ H2(2,1))) \/ H2(1,1)
by XBOOLE_1:4;
hence
X c= Y
by A75, XBOOLE_1:4;
:: thesis: verum end; end;
end;
then A113:
union H1(
w + 1)
c= union H1(
w)
by SETFAM_1:18;
let d be
set ;
:: according to TARSKI:def 3 :: thesis: ( not d in union H1(w + 1) or d in cell (Gauge D,i),m,n )
assume
d in union H1(
w + 1)
;
:: thesis: d in cell (Gauge D,i),m,n
hence
d in cell (Gauge D,i),
m,
n
by A13, A113;
:: thesis: verum
end;
for w being Element of NAT holds S1[w]
from NAT_1:sch 1(A5, A12);
hence
cell (Gauge D,i),m,n = union { (cell (Gauge D,(i + k)),a,b) where a, b is Element of NAT : ( (((2 |^ k) * m) - (2 |^ (k + 1))) + 2 <= a & a <= (((2 |^ k) * m) - (2 |^ k)) + 1 & (((2 |^ k) * n) - (2 |^ (k + 1))) + 2 <= b & b <= (((2 |^ k) * n) - (2 |^ k)) + 1 ) }
; :: thesis: verum