theorem Th66: :: SPRECT_2:66
for f being constant standard special_circular_sequence
for i, j being Nat st i in dom f & j in dom f & mid (f,i,j) is S-Sequence_in_R2 & f /. i = N-min (L~ f) & N-min (L~ f) <> NW-corner (L~ f) holds
<*(NW-corner (L~ f))*> ^ (mid (f,i,j)) is S-Sequence_in_R2