theorem Th27: :: JORDAN4:27

for f being constant standard special_circular_sequence
for g being FinSequence of (TOP-REAL 2)
for i1, i2 being Nat st g is_a_part<_of f,i1,i2 & i1 >= i2 holds
( len g = (i1 -' i2) + 1 & g = mid (f,i1,i2) )