let n be Nat; for C being connected compact non horizontal non vertical Subset of (TOP-REAL 2)
for f being FinSequence of (TOP-REAL 2)
for k being Nat st 1 <= k & k + 1 <= len f & f is_sequence_on Gauge (C,n) & not dist ((f /. k),(f /. (k + 1))) = ((N-bound C) - (S-bound C)) / (2 |^ n) holds
dist ((f /. k),(f /. (k + 1))) = ((E-bound C) - (W-bound C)) / (2 |^ n)
let C be connected compact non horizontal non vertical Subset of (TOP-REAL 2); for f being FinSequence of (TOP-REAL 2)
for k being Nat st 1 <= k & k + 1 <= len f & f is_sequence_on Gauge (C,n) & not dist ((f /. k),(f /. (k + 1))) = ((N-bound C) - (S-bound C)) / (2 |^ n) holds
dist ((f /. k),(f /. (k + 1))) = ((E-bound C) - (W-bound C)) / (2 |^ n)
let f be FinSequence of (TOP-REAL 2); for k being Nat st 1 <= k & k + 1 <= len f & f is_sequence_on Gauge (C,n) & not dist ((f /. k),(f /. (k + 1))) = ((N-bound C) - (S-bound C)) / (2 |^ n) holds
dist ((f /. k),(f /. (k + 1))) = ((E-bound C) - (W-bound C)) / (2 |^ n)
let k be Nat; ( 1 <= k & k + 1 <= len f & f is_sequence_on Gauge (C,n) & not dist ((f /. k),(f /. (k + 1))) = ((N-bound C) - (S-bound C)) / (2 |^ n) implies dist ((f /. k),(f /. (k + 1))) = ((E-bound C) - (W-bound C)) / (2 |^ n) )
assume that
A1:
1 <= k
and
A2:
k + 1 <= len f
; ( not f is_sequence_on Gauge (C,n) or dist ((f /. k),(f /. (k + 1))) = ((N-bound C) - (S-bound C)) / (2 |^ n) or dist ((f /. k),(f /. (k + 1))) = ((E-bound C) - (W-bound C)) / (2 |^ n) )
assume
f is_sequence_on Gauge (C,n)
; ( dist ((f /. k),(f /. (k + 1))) = ((N-bound C) - (S-bound C)) / (2 |^ n) or dist ((f /. k),(f /. (k + 1))) = ((E-bound C) - (W-bound C)) / (2 |^ n) )
then consider i1, j1, i2, j2 being Nat such that
A3:
[i1,j1] in Indices (Gauge (C,n))
and
A4:
f /. k = (Gauge (C,n)) * (i1,j1)
and
A5:
[i2,j2] in Indices (Gauge (C,n))
and
A6:
f /. (k + 1) = (Gauge (C,n)) * (i2,j2)
and
A7:
( ( i1 = i2 & j1 + 1 = j2 ) or ( i1 + 1 = i2 & j1 = j2 ) or ( i1 = i2 + 1 & j1 = j2 ) or ( i1 = i2 & j1 = j2 + 1 ) )
by A1, A2, JORDAN8:3;
per cases
( ( i1 = i2 & j1 + 1 = j2 ) or ( i1 + 1 = i2 & j1 = j2 ) or ( i1 = i2 + 1 & j1 = j2 ) or ( i1 = i2 & j1 = j2 + 1 ) )
by A7;
end;